Spray Crock pot with cooking spray. Trim excess fat off meat and discard. Cut Meat into 1 1/2 inch pieces, set aside.
In a bowl mix cream of mushroom soup, water and tomato paste. Put potatoes and onion in bottom of crock pot sprinkle with salt and pepper, then add the meat. Pour the soup mix on top off everything. Cook on high for 4 to 5 hours.