4 tbsp. sour cream
1 egg
sour milk (to fill cup)
1 c. sugar (scant)
1 c. flour
1 tsp. baking soda
1/2 tsp. cinnamon
1 tbsp. vanilla

Grease and dust with flour an 8-inch square pan. Preheat oven to 350°F.

Put sour cream in 1-cup measure. Add egg and fill with sour milk. Transfer to bowl and add and mix ingredients in order.

Bake at 350°F for 25 to 30 minutes. Test doneness with toothpick; stick toothpick in center of cake. Clean toothpick, done cake. Cut in squares and serve with dollop of whipped cream.