Homemade Green Bean Casserole Recipe

Name: Homemade Green Bean Casserole Recipe
Prep time: 20 min
Cook time: 40 min
Total time: 1 h
Cuisine: American
Ingredients: 1 cup panko breadcrumbs; ½ cup finely grated Parmesan cheese; Salt; Black pepper; 3 Tbsp. olive oil, divided; 1 and ½ lbs. green beans, trimmed and cut into 2-in. lengths; 8 ounces mushrooms, thinly sliced; 1 medium onion, thinly sliced; 3 Tbsp. flour; 1 (370 ml) can of 2% evaporated milk or whole milk