Baked Potato Salad

Ingredients
5 cups cold leftover mashed potatoes
3/4 cup onions, diced
3/4 cup celery, sliced
2 hard boiled eggs, chopped
1 cup mayonnaise
2 tbsp butter + greasing
1 tsp mustard powder
salt
pepper

Cooking Tools
Medium skillet
Baking dish
Medium mixing bowl

Directions
Preheat oven to 375 Degrees F.  In a skillet, melt butter and saute onions and celery for 5 minutes on low heat.  In a mixing bowl, add; mashed potatoes, the sauteed onions and celery, hard boiled eggs, mayonnaise, mustard powder, salt and pepper to taste.  Mix well and place in greased baking dish and bake in oven for 30-35 minutes.
Serves 4-6