Purpose of Egg

• In any recipe that calls for breading meat, the egg acts as a glue to keep the breadcrumbs on the chicken. You can omit the egg entirely without substituting something else, but it will be nearly impossible to get a thick coating of breadcrumbs without giving them something to stick to. This is OK in a pinch -- or when a light crust is all you want -- but for classic chicken Parmesan, thicker breading is ideal for soaking up the tomato sauce.

Butter or Oil

• For every large egg your recipe calls for, substitute about 1/4 cup of oil or melted butter. While melted butter and oil are not as viscous as egg and may not pick up as much breading, both butter and oil -- especially olive oil -- are more flavorful than egg and will add depth to your coating. Lightly flour the chicken first, as you would with any standard breading procedure, so that more butter or oil will stick to the chicken.

Mayonnaise or Yogurt

• Mayonnaise or yogurt contribute the same viscosity -- or stickiness -- as eggs, which is necessary to pick up a thick coating of breadcrumbs. Substitute about 1/4 cup of mayo or plain yogurt for each egg; any type of unflavored yogurt will work, whether full fat or nonfat, regular or Greek. Coat the chicken in an even, thin layer of mayo or yogurt to prevent the breading from falling off later. To add even more flavor, season the mayonnaise or yogurt before applying it to the chicken.

Buttermilk

• Buttermilk serves as the glue for the breadcrumbs and as a tenderizer for the chicken. In fact, you can marinate your chicken pieces in buttermilk for as long as eight hours in the refrigerator, then skip the flouring step and go straight to the breadcrumbs. Add extra flavor to the buttermilk marinade with garlic, Italian seasoning, salt and pepper.