YOUR CREAM puffs didn't puff," said the irate voice on the other end of the phone. "I did everything the recipe said."

After running down the litany of the most common problems for baking failures (Is your oven temperature accurate? Did you measure properly?), I asked the caller if she had beaten the mixture thoroughly after each addition of eggs.

"Eggs," she said. "I didn't have any eggs so I didn't use them."

If someone can leave eggs out of cream puffs and then wonder what went wrong, leaving onions out of onion soup is not beyond the realm of possiblity. On the other hand, it is often possible to make substitutions in cooking without producing failures. The secret is knowing when. And understanding that when you do subsitute your finished product will not be the same as the original. It may be better. On the other hand, it may not.

Seasoning tomato sauce with tarragon instead of basil, or using canned tomato puree instead of fresh tomatoes will produce a different flavor and texture of tomato sauce, but you will still have tomato sauce. Try leaving the sugar out of a cake, and you will obviously have an unsweetened cake. But in addition you will have a very flat cake, and one that has not browned particularly well.

Making do, which our grandmothers did so well, is a natural cooking instinct for just a few people today. For many cooks, however, it is an unattainable goal. The idea of making substitutions in a recipe sends shivers down their spines. They'd just as soon go hungry. And with the cost of food today, it's easy to understand why people don't want to make changes when they are unsure of their ground. Throwing out $10 worth of ingredients because chocolate mousse does not work when cocoa is substituted for sweet chocolate is not most people's idea of a gamble worth taking.

Americans have been taught that it is essential to follow recipes to the T or disaster will befall them; kind of a siege mentality that prevents all but the most daring of us from venturing forth on our own. It's part of the same cooking syndrome that permits us to be intimidated by advertising into believing that since we don't know how to cook, Betty Crocker (or Aunt Jemima) can do it better.

A good deal of the problem goes back to early training, or lack of it. If you didn't learn to cook at your mother's knee (20 years ago there weren't too many fathers giving lessons), it is unlikely you would learn it anywhere else. High school home economics classes, some of which admittedly have improved, taught cake baking with a box of mix: "First you open the box (a mean feat in itself), then you pour the contents into a 3-quart bowl. Add the water and the egg and beat x minutes, etc., etc."

It may be a fine lesson in opening up recalcitrant boxes, but it doesn't teach a thing about baking cakes.

For those of us who have stumbled along all of these years, afraid to make any changes, cooking in the technical, but not the creative sense, it's never too late to learn a few little tricks that can make cooking a joy instead of a chore.

Some of the information below will also make it possible to cut down on gasoline consumption. If you know how to substitute, you may not have to run back to the grocery store because you need cornstarch to thicken a sauce and all you have is flour.

ALLSPICE -- 1 teaspoon equals 1/2 teaspoon cinnamon and 1/8 teaspoon ground gloves.

ARROWROOT -- 2 teaspoons equal 1 tablespoon cornstarch.

BAKING POWDER -- 1 teaspoon equals 1/4 teaspoon baking soda plus 3/8 teaspoon cream of tartar.

BREAD CRUMBS -- 1/4 cup dry bread crumbs equals 1 slice bread; 1/2 cup soft bread crums equals 1 slice bread.

BUTTER -- 1 cup equals 7/8 cup oil or 14 tablespoons solid shortening plus 1/2 teaspoon salt.

BUTTERMILK -- 1 cup equals 1 cup yogurt.

CATSUP -- 1/2 cup equals 1/2 cup tomato sauce plus 2 tablespoons sugar, 1 tablespoon vinegar, 1/8 teaspoons ground cloves.

CHOCOLATE -- 1 ounce unsweetened equals 3 tablespoons carob powder plus 2 tablespoons water.

CHOCOLATE -- 1 ounce unsweetened chocolate equals 3 tablespoons cocoa plus 1 tablespoon butter or other kind of fat.

CHOCOLATE -- 1 ounce unsweetened plus 4 teaspoons sugar equals 1 2/3 ounces semi-sweet chocolate.

COFFEE -- 1/2 cup strong brewed coffee equals 1 teaspoon instant coffee in 1/2 cup water.

CRACKER CRUMBS -- 3/4 cup equals 1 cup bread crumbs.

CREAM -- 1 cup light cream equals 7/8 cup milk plus 3 tablespoons butter

CREAM -- 1 cup heavy cream equals 3/4 cup milk plus 1/3 cup butter. (It won't whip!)

CREAM -- 1 cup whipping cream equals 2/3 cup well chilled evaporated milk, whipped, or 1 cup nonfat dry milk powder whipped with 1 cup ice water.

EGG YOLKS -- For thickening, 2 yolks equal 1 whole egg.

FLOUR -- 1 tablespoon equals 1 tablespoon quick cooking tapioca or 1 1/2 teaspoons cornstarch, potato starch or arrowroot.

CAKE FLOUR -- 1 cup equals 1 cup minus 2 tablespoons of sifted all purpose flour.

ALL PURPOSE FLOUR -- 1 cup equals 1 1/8 cups cake flour.

SELF RISING -- 1 cup equals 1 cup all purpose plus 1 1/4 teaspoons baking powder plus 1/8 teaspoon salt.

WHOLE WHEAT FLOUR -- 3/4 cup whole wheat flour equals 1 cup white flour. When replacing whole wheat with white in baking, reduce shortening by using 2 tablespoons for ever 2 called for. Add a tablespoon or two of liquid for cakes, more for breads.

GARLIC -- 1 clove equals 1/2 teaspoon powdered, or 1 teaspoon garlic salt (reduce added salt by 1/2 teaspoon).

GELATIN -- 1/4-ounce envelope equals a little less than 1 tablespoon.

GINGER -- 1 tablespoon fresh equals 1 teaspoon powdered or 1 tablespoon candied with sugar washed off.

HERBS -- 1 tablespoon fresh equals about 1 teaspoon dried.

HOT PEPPER SAUCE -- Few drops equal dash cayenne or red pepper.

LEMON JUICE -- 1 teaspoon equals 1/2 teaspoon vinegar.

MILK -- 1 cup skim equals 1/3 cup instant nonfat dry milk plus approximately 3/4 cup water.

MILK -- 1 cup whole milk equals 1/2 cup evaported milk plus 1/2 cup water

MILK -- 1 cup whole mild equals 1 cup reconstituted nonfat dry milk plus 2 1/2 teaspoon butter (or margarine)

MILK -- in baking 1 cup whole milk equals 1 cup fruit juice.

MUSHROOMS -- 6 ounces canned, drained mushrooms equal 1/2 pound fresh.

MUSTARD -- 1 tablespoon prepared equals 1 teaspoon dried.

ONION -- 1 small fresh chopped onion equals 1 tablespoon instant minced onion or 1/4 cup frozen chopped onion.

RAISINS -- 1/2 cup equals 1/2 cup cut plumped, pitted prunes or dates.

SOUR CREAM -- 1 cup equals 3 tablespoons butter plus 7/8 cup buttermilk or yogurt.

SOUR CREAM -- for dips, 1 cup equals 1 cup cottage cheese pureed with 1/4 cup yogurt or buttermilk, or 6 ounces cream cheese enough milk to make 1 cup.

SOUR MILK -- 1 cup: Place 1 tablespoon lemon juice or distilled white vinegar in the bottom of a measuring cup. Add enough milk to make 1 cup. Stir and let mixture clabber, about 5 minutes.

SOY SAUCE -- 1/4 cup equals 3 tablespoons Worcestershire plus 1 tablespoon water.

SWEETENERS:

SUGAR -- 1 cup equals 1 3/4 cups confectioners' but do not substitute in baking.

BROWN SUGAR -- 1 cup firmly packed brown sugar equals one cup granulated sugar.

TURBINADO SUGAR -- 1 cup equals 1 cup granulated . . . with a heavier molasses flavor.

CORN SYRUP -- 2 cups corn syrup equal 1 cup granulated sugar, but according to "The Joy of Cooking," never use corn syrup to replace more than half the amount of sugar called for in a recipe. In baking, you are taking a chance in making the substitution, but if you must, "for each 2 cups of sugar, reduce the liquid called for -- other than syrup -- by 1/4 cup."

HONEY -- 1 cup equals 1 1/4 cups sugar. For baking, also decrease liquid in recipe by 1/4 cup.If there is no liquid in recipe, add 1/4 cup flour. Unless sour cream or sour milk is used in recipe, add a pinch of baking soda.

MOLASSES -- 1 cup unsulphured molasses equals 3/4 cup sugar. In baking decrease liquid by 1/4 cup for each cup of molasses, omit any baking powder and add 1/2 teaspoon baking soda.

TOMATOES -- 1 cup canned equals 1 1/3 cups chopped fresh tomatoes simmered.

TOMATO JUICE -- 3 cups equal 1 1/2 cups tomato sauce plus 1 1/2 cups water, or 1 (6 ounce) can tomato paste plus 3 cans water, dash salt, sugar.

TOMATO PASTE -- 1 tablespoon equals 1 tablespoon catsup.

TOMATO PUREE -- 1 cup equals 1/2 cup tomato paste plus 1/2 cup water.

TOMATO SAUCE -- 1 cup equals 1 can tomato paste plus 1 1/2 cans water and seasoning.

WINE -- for marinade, 1/2 cup equals 1/4 cup vinegar plus 1 tablespoon sugar plus 1/4 cup water.

WORCESTERSHIRE SAUCE -- 1 teaspoon equals 1 tablespoon soy sauce plus dash hot pepper sauce.

YEAST -- 1 cake compressed equals 1 package dried.

YOGURT -- 1 cup equals 1 cup buttermilk.