It's possible to bread a piece of meat or poultry simply by pressing crumbs to its surface, where the meat's natural moisture will hold it in place. In practice, that's seldom a satisfactory solution because the breadcrumbs quickly absorb the modest amount of moisture available, and promptly fall off when you try to cook the portions of meat. A better solution is to dip the meat or chicken in a suitable liquid, then dredge it in the breadcrumbs. Eggs are commonly used for this purpose.

Whole beaten eggs, or beaten egg whites for a lower-calorie version, work very well as an adhesive for breadcrumbs in chicken Parmesan and other recipes. The liquid content of the egg softens and moistens the crumbs, forming a uniform crust. The protein in the eggs also plays an important role in helping the crumbs adhere to the chicken. When the food hits your hot skillet, the egg proteins quickly set to a firm texture. This keeps the crumbs on the chicken, where they belong.

One alternative is to use the traditional three-stage breading technique. Dredge your chicken pieces in flour and shake off the excess. Then dip them in a shallow bowl of milk. The milk and flour form a paste, which clings to the chicken and creates a sticky surface. Dip the chicken firmly into the breadcrumbs to make an even crust. Refrigerating the chicken pieces for a half-hour after breading them will help form a better crust, ensuring that the crumb coat stays on when it's cooked. As with eggs, the starches and proteins in the milk and flour will cook first in the skillet's heat and hold the crumbs in place.

Brushing your chicken with melted butter or olive oil will help the crumbs adhere, but they'll tend to come off in patches when you turn the chicken. If you use that technique, bake the chicken pieces instead. Alternatively you can brush or spread your chicken pieces with mayonnaise, sour cream or plain yogurt. These can't be absorbed quickly by the crumbs, so they're more effective at holding the coating in place. They also contain enough protein to help secure the crumbs to the chicken. If you're using substitutes because of an egg allergy, avoid mayonnaise unless it's an eggless vegan brand.