Mashed Potato Salad

5 red potatoes
5 Yukon Gold potatoes
2 tablespoons butter
Salt and pepper to taste
1/2 cup mayonnaise
1/2 cup prepared mustard
1/2 cup sour cream
1 stalk celery, finely chopped
1 red onion, finely diced
2 small sweet pickles, finely chopped
1 green bell pepper, chopped

Cube potatoes. If desired you may peel them. Place potatoes in a large saucepan and cover with water. Cook over medium heat until potatoes are tender. Drain and place cooked potatoes in a large bowl. Mash potatoes with butter and salt and pepper to taste. Once mashed, stir in the mayonnaise, mustard and sour cream, mixing well. Stir in the celery, onion, pickles and green pepper.

Serve warm or at room temperature.