I grew up eating pierogies piled high with sour cream and onions, but turning them into a slow-cooker casserole with kielbasa made this Polish-American comfort food even easier on busy weeknights. This Crockpot Pierogi Casserole with Kielbasa layers tender pierogies, smoky sausage, and a creamy mushroom sauce, then finishes with cheddar for a melty, crowd-pleasing bake without the oven fuss.

Why you’ll love this dish

This recipe is pure, hands-off comfort. It’s perfect when you want a filling meal that practically makes itself: toss, layer, and let the slow cooker do the work. It’s budget-friendly, feeds a family, and is terrific for potlucks or busy evenings when you want something warm and homey without babysitting the stove.

“Comfort food that practically cooks itself — smoky kielbasa, soft pierogies, and cheesy goodness. Family favorite every time.” — a happy weekend supper reviewer

Reasons this stands out:

Minimal prep: mostly chopping and layering, no tricky techniques.
Great for leftovers: reheats well and freezes nicely.
Kid-friendly: familiar textures and cheesy flavor make it easy to please picky eaters.
Flexible: works with frozen or homemade pierogies and accepts simple swaps for dairy or soup.

The cooking process explained

Before you start, here’s the quick process so you know what to expect: layer half the pierogies in the slow cooker, add half the sliced kielbasa and diced onion, pour half the creamy sour-cream/mushroom soup mixture over it, then repeat. Cook on low for 6–8 hours or high for about 4, then top with cheddar to melt. That’s it—no flipping, no sauce reduction, just warm, even cooking.

You’ll want to decide up front whether to brown the kielbasa and onion first (recommended for extra flavor) or skip that step for speed. If using frozen pierogies, there’s no need to thaw—they’ll soften during the cook.

Gather these items

What you’ll need:

12 pierogies (frozen or homemade) — potato & cheese are classic; cheese-only or veggie-filled work too.
1 lb kielbasa, sliced — smoked kielbasa is common; you can use vegan sausage for a vegetarian version.
1 onion, diced — yellow or sweet onion both work.
2 cups shredded cheddar cheese — sharp cheddar gives more bite.
1 cup sour cream — or plain Greek yogurt as a tangy, higher-protein swap.
1 can (10.5–11 oz) cream of mushroom soup — cream of chicken or celery can replace it.
1/2 cup milk — any milk or unsweetened plant milk will do.
Salt and pepper to taste.
Chopped parsley for garnish (optional).

Notes and substitutions:

For a lighter dish, substitute half the sour cream with plain yogurt and use reduced-fat cheese.
To make it gluten-free, use GF pierogies and check the soup can label (or make a quick GF roux + stock).
If you prefer a richer sauce, stir in 2 tablespoons of melted butter or 1/4 cup heavy cream.

Step-by-step instructions

Spray the inside of the slow cooker lightly with cooking spray to prevent sticking.
Place half of the pierogies in a single layer on the bottom of the cooker.
Scatter half of the sliced kielbasa and half of the diced onion over the pierogies.
In a medium bowl, whisk together the sour cream, cream of mushroom soup, milk, and a pinch of salt and pepper until smooth.
Pour half of the creamy mixture evenly over the first layer.
Repeat: add the remaining pierogies, kielbasa, and onion, then pour the rest of the sauce on top.
Cover and cook on HIGH for about 4 hours or LOW for 6–8 hours. Avoid overcooking on low beyond 8 hours to prevent overly soft pierogies.
About 10–15 minutes before serving, sprinkle the shredded cheddar evenly over the top, cover, and let it melt.
Garnish with chopped parsley if desired and serve hot.

Best ways to enjoy it

Serve this hearty casserole straight from the slow cooker onto warm plates. Pairing ideas:

Crisp green salad or steamed green beans to cut through the richness.
A side of roasted Brussels sprouts or sautéed spinach for color and nutrients.
For a brunch twist, top with a fried egg per serving.
Offer sour cream, chopped chives, or pickled beets on the table for traditional complementary flavors.

For more texture, broil the casserole briefly after transferring to an oven-safe dish to get bubbly, golden cheese on top (use caution—don’t broil in the slow cooker).

Storage and reheating tips

Refrigerate: Cool to room temperature, transfer to an airtight container, and refrigerate for up to 3–4 days.
Reheat: Warm single servings in the microwave until hot throughout (stir halfway). For best texture, reheat in a 350°F oven covered for 15–20 minutes or until heated to 165°F.
Freeze: Portion into freezer-safe containers and freeze for up to 2 months. Thaw overnight in the fridge before reheating.
Food safety: Always reheat leftovers to an internal temperature of 165°F. Discard any cooked leftovers left out longer than 2 hours.

Pro chef tips

Brown for depth: Quickly pan-sear kielbasa slices and onions before layering. It adds caramelized flavor that transforms the casserole.
Avoid mushy pierogies: If you like a firmer texture, reduce cook time slightly (cook on low for 5–6 hours) or use pierogies that are not overfilled.
Even layering: Distribute kielbasa and onions evenly so every scoop gets meat, veg, and pierogi.
Don’t over-thin the sauce: Stick to the 1/2 cup milk; too much liquid makes the casserole soupy. If the casserole seems dry near the end, add 2–3 tablespoons milk or broth.
Cheese tip: Reserve 1/2 cup of cheese to add right at the end for a fresher, melty top instead of fully mixing it in earlier.

Flavor swaps

Vegetarian: Replace kielbasa with smoked tempeh, mushrooms, or seasoned roasted cauliflower. Use a vegetarian cream soup or homemade mushroom sauce.
Spicier: Stir 1/2 teaspoon smoked paprika and a pinch of cayenne into the sauce. Add sliced hot peppers with the onions.
Herby: Mix in 1 teaspoon dried thyme or a tablespoon of chopped fresh dill to brighten the flavors.
Broader mix-ins: Add a cup of frozen peas or a cup of sliced mushrooms with the onions for more veggies.
Cheesy variations: Swap half the cheddar for smoked gouda or Monterey Jack for a different cheese profile.

Your questions answered

Q: Can I use fresh pierogies instead of frozen?
A: Yes. Fresh pierogies will cook faster and retain a firmer texture; watch the time and check for tenderness after 4–5 hours on low.

Q: Do I need to brown the kielbasa first?
A: No — kielbasa is usually pre-cooked, so it will heat through safely in the slow cooker. Browning is optional but adds flavor and texture.

Q: Will the pierogies become too mushy in the slow cooker?
A: They can if overcooked. Stick to the recommended times (high ~4 hours, low 6–8 hours) and avoid leaving the cooker on low much beyond 8 hours.

Q: Can I make this in a casserole dish in the oven?
A: Yes. Assemble in a greased baking dish and bake at 350°F for 30–40 minutes, covered, then uncover and bake 10 minutes more until bubbly and golden.

Q: Is this freezer-friendly?
A: Absolutely. Freeze assembled (uncooked) in a freezer-safe dish for up to 2 months. Thaw overnight before cooking, or extend cooking time to ensure even heating.

Conclusion

If you want a set-it-and-forget-it comfort meal that’s flavorful, flexible, and family-friendly, this Crockpot Pierogi Casserole with Kielbasa is a winner. For another take on the same idea and extra tips, see this detailed version from Crockpot Pierogi Casserole with Kielbasa – That Oven Feelin. If you’d like a slightly different twist with cheesy layers and step photos, check out Crock Pot Pierogi and Kielbasa Casserole – The Country Cook for inspiration.

Enjoy — and feel free to ask if you want help swapping ingredients for dietary needs or scaling this for a crowd.