4 med. size red skin potatoes, peeled and quartered
3 tbsp. milk
4 tsp. butter
1 egg yolk
1/4 tsp. salt
1/8 tsp. black pepper

Boil potatoes until tender. In a small saucepan heat milk and stir in butter. Drain potatoes and mash, then beat in egg yolk and milk mixture, add salt and pepper to taste.