Banana Cake

2 1/2 cup flour
1 1/2 cup sugar
1 tsp. salt
2/3 cup oil
1 1/4 cup mashed banana
2 eggs
1 1/4 tsp. baking powder
1 tsp. soda
1/3 cup buttermilk

Mix, adding buttermilk last. Bake at 350 for 25 minutes in a 9x13 inch pan or 20 minutes in a cookie sheet. (Optional: 1 cup chopped walnuts)

Frosting:

2 Tb. butter
6 oz cream cheese
4 cups powdered sugar
2 tsp vanilla