Egg yolk

The dark yellow to orange thick substance located in the center of an egg. The egg yolk contains protein, fat and most of the vitamins in an egg including iron, vitamins A and D as well as phosphorus, calcium, thiamine, and riboflavin and lecithin.

Egg substitute

1 egg yolk = 1 1/2 tbsp OR 1 cup = 12 large egg yolks