Are you ever in the middle of a recipe and realize a specific seasoning is missing from the spice rack? Check out these spice substitutions if you're ever in a bind.

Crème fraîche is all the rage these days, but what is it and what do you do if you can't find it?

You don't always have the baking pan that a recipe calls for, but here's what you can do when you need to use something else.

Looking for a way to make your baking chocolate taste better?

Everyone's been there. You're going along, assembling the ingredients for your cake, and...your heart sinks. You don't have any baking powder! Frantically, you toss things aside in the fridge, desperate for any crumbs of the stuff...but you find nothing.

Don't panic - just substitute. (Well, you can still panic if it will make you feel better, but it's really not necessary). Instead, just use 1/4 tsp. soda plus 1/2 tsp cream of tartar, or 1/4 teaspoon soda plus 1/2 cup sour milk or buttermilk.
And speaking of which, what do you do if you're out of buttermilk?

Here are some of the substitutions I've found most helpful.

• Instead of one cup of buttermilk, add 1 tablespoon vinegar to slightly less than one cup of milk.
  
• Instead of 1 cup of cake flour, try 7/8 cup all-purpose flour plus 2 Tbsp. cornstarch
• Instead of 1 tsp. dried leaf herbs, try 1/4 tsp. powdered herbs
• Instead of 1 cup of honey, use 1/ 1/4 cups sugar and 1/4 cup of liquid
• Instead of 1 Tbsp. cornstarch, use 2 Tbsp. flour or 1 1/3 Tbsp. quick-cooking tapioca.
  

What substitutions have you used in a pinch?

Yesterday, I talked about the Cook's Illustrated review of egg white substitutes, which concluded that you are best off working with real, fresh egg whites. The pre-packed, pasteurized egg white substitutes didn't hold up when whipped as well as the real thing. There is one more type of egg white substitute that is known for its ability to whip up, though: meringue powder.

Meringue powder is a mixture of dried, powdered egg whites, cornstarch and gums, which help if bind together. Some powders include sugar, but the majority do not. When mixed with sugar and water, meringue powdered can be reconstituted and beaten to soft or stiff peaks. It can be used to make royal icing, baked meringues, and even angel food cakes, which I have tried with good success. It can not be substituted for egg whites in other recipes, though, only in recipes which call for beaten egg whites. Meringue powders, other than being used for frosting, are best used in recipes where the egg whites would have been uncooked, like in some mousses and sorbets. Keep in mind that meringue powder can have a sort of starchy aftertaste from the cornstarch, so don't reduce the amount of sugar or other flavorings in the recipe you're using unless you want to add another flavor to your dessert.

I often get asked whether substitutions can be made in a recipe. Baking is really a sort of science experiment, much more so than actual cooking, so while substitutions will work sometimes it is often best to simply follow the recipe, if at all possible. I never thought to devote an entire post to the subject, instead answering inquiries on a one-on-one basis, but Rose Levy Beranbaum finally said what I, and other bakers, have been thinking for a long time:

Can you substitute ingredients? Yes. Should you? Usually, no.

There are many parts of recipe for breads, cookies and cakes that cannot change without fundamentally altering the final product. For example, if a recipe calls for baking powder you cannot substitute yeast. They may both be leaveners, but they are completely dissimilar. You could try to substitute whole wheat flour for all purpose, but the outcomes will not be identical because the properties of each type of flour are different. Flavorings and add-ins, like chocolate chips, blueberries, nuts or vanilla extract, can be substituted for other, similar ingredients, but the mainstays of a recipe should not be changed if you are expecting to reproduce the outcome of the original recipe. Rose suggests changing one ingredient at a time, if you really want to experiment, and watching the results. You might not get edible cookies, but you will gain a better understanding of how your ingredients work should you want to make changes in the future. Websites like FoodSubs.com can help, but if you want chocolate cake right now, try to stick with the recipe for the best results.

Sometimes when you're cooking, you've got to make substitutions. Either you don't have an ingredient on hand, or perhaps a guest cannot eat a particular ingredient. This can occur with alcoholic drinks as well. Don't fear, because the Gourmet Sleuth has a list of substitutions for alcohol in cooking. The list is pretty extensive, including everything from red wine to cognac to sherry. As you can imagine, the wines are typically replaced with a mixture containing white or red grape juice, and many of the higher alcohol content spirits are replaced with vanilla (non-alcoholic), sparkling cider, or even coffee. The point of all this is to give the dish the acidity and intense flavors that are usually added through alcohol. I'm sure that some of them work better than others. Does anyone have any particular anecdotes about alcoholic substitutions that work?