Directions
Spray the inside of your slow cooker with nonstick cooking spray or lightly grease it with butter or oil to help prevent sticking.
Place half of the frozen pierogi in an even layer on the bottom of the slow cooker. It’s okay if they overlap a bit.
Scatter half of the sliced kielbasa over the pierogi, then sprinkle with 1 cup of the shredded cheese.
Repeat the layers with the remaining pierogi, kielbasa, and the last 1 cup of shredded cheese.
Pour the heavy cream or half-and-half evenly over the top, trying to cover as much of the pierogi and cheese as possible. Don’t stir; the liquid will work its way through as it cooks.
Cover and cook on LOW for 3–4 hours, or until the pierogi are tender and heated through, the cheese is melted, and the sauce is bubbly around the edges. (Avoid lifting the lid too often so you don’t lose heat.)
Once done, gently stir from the edges toward the center to coat the pierogi in the creamy sauce without breaking them up too much.
Let the casserole sit for about 5–10 minutes with the lid off to thicken slightly, then serve warm straight from the slow cooker.
Variations & Tips
• Lighter swap: Use half-and-half instead of heavy cream to cut some richness, or do 1 cup cream and 1 cup milk. You’ll still get a creamy sauce, just a bit lighter. • Extra flavor boost: If you have more than four ingredients on hand, add 1 small sliced onion and 2–3 minced garlic cloves to the layers for more depth. A pinch of black pepper or paprika over the top before cooking is also great. • Bacon lovers: Stir in 1/2–3/4 cup cooked, crumbled bacon at the end of cooking for a smoky, salty finish. It’s especially good if you’re using cheddar cheese. • Veggie add-ins: To sneak in some vegetables, layer in 1–2 cups of frozen peas, corn, or mixed veggies along with the pierogi and kielbasa. They’ll cook right along with everything else. • Different pierogi: This works with almost any savory frozen pierogi—potato and onion, potato and cheddar, or even sauerkraut if you like a tangier flavor. Just keep the total amount about the same. • Make-ahead tip: You can assemble all the layers in the slow cooker insert the night before, cover, and refrigerate. In the morning, set the insert in the base, add an extra 10–15 minutes to the cook time, and let it go while you’re working. • Crispy finish: If you like a browned, bubbly top, transfer the cooked casserole to a baking dish, add a little extra cheese, and broil for 3–5 minutes until golden.
