Can i substitute mayo for an egg?!

Mayo can be substituted for oil in a cake recipe. But not for eggs.

Only one egg, yes. Eggs release steam as they cook, and this steam "puffs up" the dough so it doesn't end up really tough and dense. Even just one egg. You won't like your brownies without that egg.

Yeah, wait until you have an egg.

duck egg Notes: Compared to chicken eggs, these are larger, higher in fat, more colorful, and more flavorful. They're sometimes contaminated with bacteria, so make sure you cook them thoroughly. Substitutes: chicken egg (smaller and not as oily, colorful, and flavorful)



egg = chicken egg Equivalents: One egg contains about one tablespoon of egg yolk and two tablespoons of egg white and weighs about two ounces without the shell. Varieties: Eggs come in different sizes. Most recipes assume that you're using large eggs. To substitute larger or smaller eggs in recipes, visit the Basic Egg Facts page. Also available are reduced cholesterol eggs (sold in the shell), powdered eggs, and liquid pasteurized eggs (sold in cartons). Equivalents: 1 whole egg = 2 egg whites (to reduce fat; may make baked goods less tender) = 2 egg yolks (in sauces, custards, and cream fillings). One egg contains about one tablespoon of egg yolk and two tablespoons of egg white.

You could do either, I would probably leave the egg out; they will just be a bit more dense. Mayo is mostly oil. It may add an interesting flavor, but it will add a little extra salt as well.

Or you could malke 1/2 or 3/4 (since you have 3 of the 4 eggs needed) of the recipe, and just bake it in a smaller pan.

Mayo is whipped egg whites but it also has some other stuff in there.
You can also use cornstarch if you want. 2 TBS = 1 EGG