🧀 Crockpot Pierogi Casserole with Kielbasa If comfort food had a slow-cooker version, this would be it. Cheesy pierogi, smoky kielbasa, and a creamy sauce come together in one easy, cozy dish that basically cooks itself. Perfect for busy nights or lazy weekends. 🛒 Ingredients (Serves 4–6) For the casserole 1 (16 oz) package frozen cheese pierogi 14 oz kielbasa sausage, sliced 1 medium onion, diced 2 cups shredded cheddar cheese 1 cup shredded mozzarella cheese For the sauce 1 cup sour cream 1