1 lg. can canned yams
1/2 stick butter
1 tsp. vanilla
1 egg
1 tbsp. sugar
1 can crushed pineapple
Marshmallows

Mash sweet potatoes; then mash in butter. Add vanilla, egg, and sugar.

Butter casserole dish; put crushed pineapple on bottom and add potato mixture. Garnish with marshmallows. Bake in medium oven until heated through.