Cooking Pasta: Cook the pasta just until it's al dente; it will continue to cook in the slow cooker and you don’t want it to become mushy. Cheese Options: Feel free to mix different types of cheeses based on your preference. For added flavor, you could use smoked mozzarella or add a sprinkle of red pepper flakes for heat. Make It Vegetarian: Omit the meat and substitute with additional vegetables such as spinach, bell peppers, or mushrooms for a hearty vegetarian option. Store leftovers in an airtight container in the refrigerator for up to 3-4 days. Reheat in the microwave or oven until warmed through. You can also freeze the baked ziti for up to 3 months. Thaw in the refrigerator overnight before reheating.