Since the chicken breasts I had on hand were quite different in size and thickness, I decided to brown the stuffed breasts on each side, then finish off baking them in the oven rather than frying to completion. Given how generously I stuffed the breasts, I think this is a safer option. There's nothing I hate more than undercooked or unevenly cooked meat.
2+ tablespoons extra virgin olive oil
1-2 teaspoons garlic, minced
1/2 medium cooking onion, diced
4-6 ounces cremini mushrooms, diced
1/2 - 3/4 cup fresh spinach leaves, chopped
Kosher salt and cracked pepper, to taste
1 1/2 tsp Mrs. Dash Italian Medley
1/2 cup mozzarella cheese, shredded
2 skinless/boneless chicken breasts, trimmed of fat
In a large pan, heat 1 tablespoon olive oil until lightly smoking. Add the garlic and cook until fragrant, about 30 seconds. Add the onion and cook until slightly translucent, about 2 minutes. Add the mushrooms and spinach and cook for another 3 minutes. Season with salt and pepper to taste. Remove vegetables from heat. Stir in mozzarella cheese and mix until incorporated.
Using a sharp knife, slice a slit into the side of each chicken breast. Move the knife back and forth to make a pocket. Rub the chicken liberally with EVOO on both sides, then season with salt, pepper and the Italian Medley. Stuff each chicken breast with some of the mushroom mixture. Use wooden toothpicks to keep the stuffing from falling out.
In a large pan over medium-high heat (not high as the cheese doth runneth over and will make a mess), heat the remaining 1 tablespoon olive oil until lightly smoking. Add the chicken breasts and cook on one side until nicely browned, about 5-8 minutes depending on the thickness of the chicken. Carefully flip the chicken breasts over and cook on the other side for another 5-6 minutes until browned.
Remove stuffed breasts to baking pan sprayed with Pam or line with foil. Bake at 350 deg for 20-25 minutes until cooked through.
Note: Be prepared for a little elbow-grease clean-up as the cheese is ooey-gooey good and tends to get everywhere!