01 -
Spray the interior of the crockpot with nonstick cooking spray. Arrange half of the frozen pierogies in an even layer at the bottom.
02 -
Distribute half of the sliced kielbasa and diced onions evenly over the pierogies.
03 -
In a medium bowl, blend the condensed cream of mushroom soup, sour cream, garlic powder, and black pepper until smooth.
04 -
Spread half of the soup mixture over the first layers. Repeat layering with the remaining pierogies, kielbasa, onion, and sauce.
05 -
Sprinkle shredded cheddar cheese over the top. Cover and cook on low heat for 4 hours, until the casserole is heated through and bubbly.
06 -
Optionally garnish with chopped fresh parsley before serving.