Shirley O. Corriher is the Dr. Gregory House of the cooking world.

She's a culinary diagnostician.

Rice sinking to the bottom of your pudding? Dust it with corn starch first.

Cookies too flat? Swap out some of the butter for shortening.

Custard too watery? Reduce the sugar and add another egg yolk.

Her current patient is a pumpkin flan recipe sent to her by a Texas chef. It fails to set up in the center. So far, Corriher hasn't been able to figure out what's wrong. It could be that some enzyme in the pumpkin is interfering, it could be the ratio of sugar to eggs, it could be any number of things.

''I'll figure it out. I've only been working on it a week,'' Corriher said.

At 74, Corriher is going strong, teaching, consulting and writing, despite a ''titanium knee'' that makes getting around a bit challenging for her.

Her latest book, BakeWise: The Hows and Whys of Successful Baking, ($40 hardcover, Scribner) released in November, walked away with the James Beard Foundation Award for best cookbook in the Baking and Dessert category on May 4.

A week later she was at the Western Reserve School of Cooking in Hudson to teach a two-day series of classes on baking, based on the book.

When I sat down with Corriher, she still had the Beard Award stored in a zipper-lock plastic bag in her purse, and she laughed that she had to resist the urge to wear the heavy bronze medallion that hangs from a bright orange grosgrain ribbon.

Corriher isn't a chef, but her number had been on speed dial for some of the most notable — Julia Child and Jacques Pepin, to name two. She has consulted for the Pillsbury test kitchen, is a frequent guest on Alton Brown's Good Eats show on the Food Network, and has solved more culinary mysteries than Nancy Drew and Jessica Fletcher combined.

Corriher has a degree in chemistry from Vanderbilt University, but it was only after a divorce and years of financial struggle to raise three children on her own that she found her way into Rich's Cooking School in Atlanta in the 1970s.

Corriher started out taking classes at the school, run by famous Atlanta chef and cookbook author Nathalie Dupree. But Dupree eventually hired Corriher to help set up cooking classes and clean up after. It wasn't long before Corriher distinguished herself by being able to offer scientific explanations for culinary puzzles, and her career began to develop.

Her first book, CookWise: The Hows and Whys of Successful Cooking ($34.99 hardcover, William Morrow), also won the Beard Award and is considered a must-have kitchen companion for many chefs and home cooks.

Her classes in Hudson were sellouts and her students seemed as enchanted by her storytelling as they were by her explanations for how to make their baked goods turn out better.

Corriher is an expert storyteller, and her honeyed Southern accent enhances her delivery. She tells the class how her first venture into cooking was mud pies, leavened with chicken feed, made with her childhood sweetheart at her grandmother's home in
Conyers, Ga.

She gets laughs with tales of the first time she tried sugar pulling and ended up with second-degree burns on her fingers.

But she brings down the house when she describes her 2003 appearance on Jimmy Kimmel Live: She was invited to batter-fry a variety of items, including a PopTart, a whole sub sandwich, chocolate bunnies, ping-pong balls, a banana, and the wristwatch of an audience member, with Kimmel as her assistant and rapper Snoop Dogg as her fry cook.

In between stories, she manages to impart a lot of culinary knowledge.

Corriher comes alive when explaining the process by which gluten forms, a topic that resurfaces over and over again as she gives her pastry hints. It is key to understanding how to change the composition of pastries.

Gluten forms when the two proteins in flour — glutenin and gliadin — combine with water. As the flour is stirred, the proteins connect to form sheets of gluten, she explains, using her hands and fingers to show how the proteins grab on to the water.

Ever bite into a Wedding Cookie (sometimes called Butter Balls or Russian Tea Cookies) only to have the entire ball crumble, leaving you coated in powdered sugar? The problem is that the butter coats the proteins in the flour, so they can't grab on to the moisture and form gluten.

Her solution: Just sprinkle a little water over the flour before you begin making the dough. Gluten will begin to form, causing the cookies to be less crumbly, Corriher said.

''If you make the gluten before you add the butter, you already have a little gluten there,'' she said.

Corriher has figured out why the original recipe for Nestle's Toll House Cookies will always produce flat cookies — the butter melts too quickly when placed in the hot oven. To prevent this, she recommends replacing half of the butter with butter-flavored shortening, which melts more slowly, allowing the cookies to not spread into ''crepes with chips.'' Always use a high-protein flour and always chill the dough, which also helps to keep cookies from spreading.

Cookies, Corriher said, can be a challenge because they are a low-moisture situation that ''magnifies anything.''

''That's the thing with cookies, every little thing you do to them changes them,'' she said.

Some of Corriher's advice is practical: Never bake powdered sugar cookies, such as Chocolate Crinkles, in a convection oven — the fan will blow the sugar all over the place.

Other hints come from years of testing and re-testing recipes to find out how to control the outcome for the best result:

• Resist the urge to open the oven door when baking. Oven temperature can drop as much as 100 degrees in 10 seconds. The change can ruin a cake or cookie.

• Too much sugar and a cake will sink.

• The correct amount of leavening is 1 teaspoon of baking powder to 1 cup of flour, or 1/4 teaspoon of baking soda to 1 cup of flour. Baking soda, however, requires an acid in the batter, such as buttermilk, for it to work.

• White sugar will produce a crispier cookie, while brown sugar will produce a softer, puffier cookie.

• The addition of corn syrup will produce a more fudge-like result in chocolate cookies and brownies. The addition of corn syrup, even just a tablespoon, also will aid in browning if cookies turn out too pale.

• Too much sugar can make a cookie or batter brown too quickly. If you've ever eaten an onion ring that was browned, but the onion inside was still raw, chances are there was sugar in that batter that overbrowned the coating before the onion could cook.

• Salt will suppress bitterness to bring out the sweetness in brownies.

• The shiny crust that forms on top of brownies is actually meringue. It is caused by the batter being beaten after the eggs are added. ''The more you beat, the more crust you get,'' Corriher says.

• Brownies are fudge-like or cake-like depending on their ratio of flour to fat. For more cake-like brownies, increase the flour; for a more fudge-like result, decrease the flour and increase the fat.

Here are a few of Corriher's cookie recipes and her cooking notes that accompany them.

BUTTERY JELLY JEWELED COOKIES
1 cup unsalted butter, cut into 2-tablespoon-size pieces
1/2 cup sugar
1/4 tsp. salt
1/4 tsp pure almond extract
2 large egg yolks
21/4 cups spooned and leveled, bleached all-purpose flour
1/4 cup good preserves, such as dark cherry

In a heavy-duty mixer with the paddle attachment, beat the butter, sugar, salt and almond extract until light and creamy. Add the yolks, one at a time, and beat with each addition, just to blend in thoroughly. On the lowest speed, beat in the flour, scraping the bowl down and across the bottom twice. Divide the dough into 4 pieces. Roll each into a log about 11/2 inches in diameter. Wrap each roll individually in plastic wrap and refrigerate at least 2 hours or overnight.

Heat and strain the preserves.

Thirty minutes before you are ready to bake, preheat the oven to 375 degrees and place a shelf in the center of the oven.

Cover a heavy baking sheet with release foil, nonstick side up; a silicone baking sheet or parchment paper.

Slice cookies into 3/8-inch thick slices and arrange about 1 inch apart on the sheet. Immediately after you slice each cookie and place it on the baking sheet, press an indentation in the center with your thumb or fingertip.

After all the cookies are on the sheet, carefully spoon or pipe a small amount of jelly to fill the indentation in each cookie.

Place the baking sheet on arranged shelf. Bake one sheet at a time until the edges just begin to brown, about 14 minutes. Slide the foil sheet onto a cooling rack to cool.

Makes about 3 dozen cookies.

Notes: This batter has a relatively small amount of sugar for a cookie, so a tiny bit of jelly is a perfect finishing touch to add both sweetness and flavor. The relatively small amount of sugar and just a touch of flavoring allow the flavor of the butter to dominate.

By baker's percentages, these cookies are 75 percent butter, but because they have practically no liquid — 1/4 teaspoon of almond extract, with alcohol which evaporates fast, and less than a tablespoon of water from the egg yolks — they do not spread much. Having the dough cold also helps to limit spread.

CHOCOLATE CRINKLE COOKIES
13/4 cups plus 2 tbsp. spooned and leveled, bleached all-purpose flour
11/2 tsp. baking powder
1/2 tsp. salt
8 oz. semi-sweet chocolate, finely chopped
23/4 cups sugar, divided
1/3 cup canola oil
2 tbsp. light corn syrup
2 large eggs
1 large egg yolk
2 tsp. pure vanilla extract
1 cup confectioners sugar

In a medium bowl, beat together well flour, baking powder and salt and set aside.

Melt chocolate in the microwave on 50 percent for 1 minute, stir, and microwave for 15 seconds more and stir.

In the mixer with paddle attachment, beat 21/2 cups sugar, oil, and corn syrup together to blend. Beat in eggs, egg yolk and vanilla, and on low, then beat in melted chocolate. Add flour mixture and beat in on low.

Wrap the dough in plastic and refrigerate for about an hour.

About 30 minutes before you are ready to bake, arrange a shelf in the middle of the oven and preheat the oven to 325 degrees.

Take out about 1/4 of the dough at a time to shape. Roll the dough into 11/2- to 2-inch balls. Pour 1/4 cup granular sugar into one bowl and the confectioners' sugar in another bowl. Roll each cookie dough ball very lightly in plain sugar first and then very heavily in confectioners' sugar (see note).

Place release foil (nonstick side up) on a baking sheet. Arrange cookies 2 inches apart. For crisp cookies, bake 12 to 14 minutes, or slightly less time for a softer center. You can have several sheets of foil covered with cookies ready.

When one sheet is done, you can pull off the foil and cookies to a cooling rack. Rinse baking sheet with cold water to cool and then slip the sheet under a foil with cookies and get it right back into the oven.

Makes 3 to 5 dozen depending on size.

Notes: You can change the sweetness of these cookies just by substituting 2 to 4 ounces of 60 percent chocolate for 2 to 4 ounces of the semi-sweet.

Rolling in plain sugar first ensures the confectioners' sugar does not soak in so much and stays on the surface better.

Corn syrup in the batter helps prevent crystallization to produce the soft chocolate center.

Oil greases flour proteins to produce a tender-to-the-point-of-gooey chocolate center.

WEDDING COOKIES
1 cup unsalted butter
21/2 cups confectioners' sugar, divided
1 tbsp. pure vanilla extract
1 tbsp. water
2 cups all-purpose flour
1/4 tsp. salt
3/4 cup finely chopped pecans

Place a rack in the center of the oven and preheat the oven to 325 degrees.

Cover a baking sheet with release foil (nonstick side up), a silicone baking sheet or parchment paper. In a heavy-duty mixer with the paddle attachment, beat butter and 1/2 cup confectioners' sugar until fluffy. Beat in vanilla.

In a medium mixing bowl, sprinkle the water over the flour and stir, then stir in the salt. Add the flour mixture to the mixer in several batches and beat on the lowest speed just to blend in. When all the flour is added, add the pecans.

Roll the dough into balls about the size of a walnut and place on the baking sheet about 1 inch apart. Bake until set but not browned, about 20 minutes.

While the cookies are warm, lift them with a spatula, one at a time, into a large mixing bowl with 2 cups confectioners' sugar. Gently roll them in the confectioners' sugar several times to coat generously, then place on a rack to cool. Re-roll once again in confectioners' sugar before storing.

Makes about 4 dozen cookies.

Notes: A tablespoon of water is sprinkled over the flour and stirred in to make a little gluten to limit crumbling of these delicate cookies. These cookies are notoriously crumbly because of the large amount of finely chopped nuts and the fact that, in a traditional recipe, the only water in the recipe is in the butter.
— All recipes from Shirley Corriher, BakeWise

Lisa A. Abraham can be reached at 330-996-3737 or labraham@thebeaconjournal.com.