Pound the chicken breasts: Place each chicken breast between two sheets of plastic wrap. Using a meat mallet, pound them to an even thickness of about ½ inch.

Season your chicken: Sprinkle both sides generously with salt and pepper.

Set up your breading station: In one shallow dish, place the flour. In another, beat the eggs. In a third, mix the breadcrumbs with the Parmesan cheese.

Dredge each chicken breast in flour, shaking off the excess. Then dip it in the beaten eggs, and finally coat it with the breadcrumb mixture.

In a large skillet, pour enough olive oil to cover the bottom (about ¼ inch deep). Heat over medium-high heat.

Add the breaded chicken carefully to avoid splashes. Cook for about 3-4 minutes on each side until golden brown and cooked through. Keep warm on a plate lined with paper towels.

In the same skillet, melt the butter over medium heat. Add the chopped onion and mushroom slices, cooking until the mushrooms are tender and onions are translucent (about 5 minutes).

Stir in the minced garlic and cook for another minute. Sprinkle flour over the mixture and stir. Gradually add chicken broth, stirring to combine.

Add Worcestershire sauce, salt, and pepper to taste. Allow it to simmer until thickened, about 5 minutes.