Spray a crockpot or slow cooker with cooking spray or use a slow cooker liner for easy cleanup.
Add the frozen Potatoes O’Brien with peppers and onions directly to the crockpot. If using canned or frozen diced potatoes, drain well before adding.
Slice kielbasa into thin rounds and distribute over the potatoes. Any kielbasa or smoked sausage variety can be substituted.
Pour in the cream of chicken soup and ranch seasoning packet or your chosen seasoning mix. If desired, add melted butter, chicken broth, or heavy cream to enhance creaminess.
Stir all ingredients thoroughly to combine.
Cover and cook on low heat for about 4 to 6 hours, checking at 4 hours to avoid overcooking. Alternatively, cook on high for 3 to 4 hours. Cooking time may vary depending on your crockpot.
Once the potatoes are tender and fully cooked, sprinkle the shredded cheese evenly over the top. Let it melt for a few minutes in the crockpot.
Before serving, garnish with chopped green onions and optional red pepper flakes if desired.