Creamy Garlic Parmesan Chicken Breasts with Mushrooms

Name: Creamy Garlic Parmesan Chicken Breasts with Mushrooms
Cuisine: European, Italian, Mediterranean
Ingredients: 2 large chicken breasts, sliced horizontally; 1/2 lb (225g) mushrooms, sliced; 3 tablespoons butter, divided; 1 tablespoon olive oil; Salt and pepper to taste; 1 teaspoon oregano; 1 medium onion, minced; 4 cloves garlic, minced; 2 tablespoons marinara sauce (or your favorite tomato sauce); 1/2 cup chicken broth; 1/2 cup whipping cream or heavy cream; 1/3 cup grated Parmesan cheese; 1 teaspoon fresh chopped parsley and red chili pepper flakes, for garnish