Combine the peas, water chestnuts, cheese, and green onions together in large bowl. Mix the mayonnaise and sour cream well (can add a little more sour cream; use your own judgment). Mix this mixture with the peas, water chestnuts, cheese and green onions. Add salt and pepper. Either sprinkle the crumbled bacon on top or mix in with the salad.
This is best if chilled several hours before serving. ENJOY!