01 -
Spray the inside of your slow cooker lightly, so nothing gets stuck later.
02 -
Toss in half the onion, then pile on half the sliced kielbasa. Cover them with half your pierogi.
03 -
Take a bowl and stir together the sour cream, melted butter, and cream of mushroom soup until you see no lumps.
04 -
Drizzle half your creamy sauce all over the stuff you've layered so far.
05 -
Now add what's left: pierogi, then the last of the onion and kielbasa, with the rest of the sauce poured on top.
06 -
Pop on the lid and cook everything on low for 4-5 hours till your pierogi are nice and soft.
07 -
About 30 minutes before it's done, sprinkle cheddar cheese all over, then put the lid back until it melts perfectly.
08 -
Add some salt and pepper right before serving. Throw chopped chives on top if you want and dig in while it's still hot.