Parmesan Potato Wedges

2 pounds red potatoes, cut into 1/2 inch wedges
1/4 cup finely chopped yellow onion
1 1/2 tsp. dried oregano
1/2 tsp. salt
1/4 tsp black pepper, or to taste
2 tblsp. butter, cut into 1/8- inch pieces
1/3 cup grated Parmesan cheese

Layer potatoes, onion, oregano, salt, pepper, and butter in crock pot. Cover and cook on High for 4 hours. Transfer potatoes to serving platter and sprinkle with cheese.