Frosted Banana Bars

1/2 cup butter, softened
1 1/2 cups sugar
2 eggs
1 cup (8 ounces) sour cream
1 teaspoon vanilla extract
2 cups flour
1 teaspoon baking soda
1/4 teaspoon salt
2 medium ripe bananas, mashed (about 1 cup)

Frosting:
1 package (8 ounces) cream cheese, softened
1/2 cup butter, softened
2 teaspoons vanilla extract
3 3/4 to 4 cups confectioners' sugar

In a bowl, cream butter and sugar. Add the eggs, sour cream and vanilla. Combine the flour, baking soda and salt; gradually add to the creamed mixture. Stir in bananas. Spread into a greased 15x10 baking pan. Bake at 350 degrees for 20-25 minutes or until a toothpick inserted near the center comes out clean. Cool. For frosting, in a bowl, beat the cream cheese, butter and vanilla. Gradually beat in enough confectioners' sugar to achieve desired consistency. Frost bars. Store in the refrigerator.