Ingredients
2 (16-ounce) boxes frozen potato-and-cheese pierogies
1 (14-ounce) ring kielbasa, sliced into 1/2-inch coins
2 cups heavy cream
2 cups shredded sharp cheddar cheese, divided
Directions
Lightly grease the inside of a 4- to 6-quart slow cooker with cooking spray or a little butter so the cheesy sauce doesn’t stick too much.
Spread one box of frozen pierogies in an even layer on the bottom of the slow cooker. It’s fine if they overlap a bit; keep them in a single, fairly even layer so they cook evenly.
Scatter half of the sliced kielbasa over the pierogies, tucking some pieces down between them so you get a little sausage in every scoop later.
Sprinkle 1 cup of the shredded cheddar cheese evenly over the kielbasa and pierogies.
Repeat the layers with the second box of frozen pierogies, the remaining sliced kielbasa, and another 1/2 cup of the shredded cheddar, reserving the last 1/2 cup of cheese for the end.
Pour the heavy cream slowly and evenly over the top, letting it seep down into the layers. Do not stir; the cream will create a rich, silky sauce as everything cooks.
Cover the slow cooker with the lid and cook on LOW for 3 1/2 to 4 hours, until the pierogies are tender and puffed, the kielbasa is hot, and the cream has thickened into a cheesy, bubbling sauce around the edges.
About 15 minutes before serving, gently lift the lid and sprinkle the remaining 1/2 cup shredded cheddar over the top. Cover again and cook just until the cheese is fully melted and the top looks golden and glossy around the edges.
Once the cheese is melted and everything is hot and bubbling, turn the slow cooker to WARM. Let the casserole rest, covered, for about 5 to 10 minutes so the sauce thickens slightly, then serve big spoonfuls straight from the crock into warm bowls.
Variations & Tips
For a little onion flavor without adding more ingredients, choose a smoked kielbasa that’s seasoned with garlic or onion; it will perfume the whole dish as it cooks. If you prefer a slightly lighter version, you can swap half of the heavy cream for whole milk, though the sauce will be a bit looser and less rich. Use extra-sharp cheddar for a bolder, tangier cheese flavor, or a mild cheddar if you’re cooking for little ones. If you like a bit of browned top, transfer the cooked casserole to a baking dish, sprinkle with an extra handful of cheese (from your own pantry, beyond the base four ingredients), and broil for a few minutes until golden and blistered. Leftovers reheat well in the microwave; add a spoonful of milk or cream before reheating to bring back the silky texture. To stretch the meal for a crowd without changing the core recipe, serve smaller scoops over a bed of steamed cabbage or alongside a big bowl of coleslaw for that classic Midwest table feel.