Banana Cake

While we were visiting our good friends, Sarah and Tyler, over Thanksgiving, she made this cake.  I am not normally a huge banana lover, but it was as if I couldn't get this stuff in to my mouth fast enough.  I must have eaten at least 2 very large pieces each day that it was sitting in front of me.  It is moist and banana-y and who doesn't love stuff with cream cheese frosting?
Make it.  I challenge you to not like it.

1 1/2 c. bananas, mashed
2 tsp. lemon juice
3 c. flour
1 1/2 tsp. baking soda
1/4 tsp. salt
3/4 c. butter
2 1/8 c. sugar
3 large eggs
2 tsp. vanilla
1 1/2 c. buttermilk

1/2 c. butter, softened
1 (8 oz.) pkg. cream cheese, softened
1 tsp. vanilla
3 1/2 c. powdered sugar

1.  Preheat oven to 275.  Grease and flour a 9X13 inch baking pan.
2.  In a small bowl, mix mashed banana with the lemon juice; set aside.  In a medium bowl, mix flour, baking soda and salt; set aside.  In a large bowl, cream 3/4 c. butter and 2 1/8 c. sugar until light and fluffy.  Beat in eggs, one at a time, then stir in 2 tsp. vanilla.  Beat in the flour mixture alternately with the buttermilk.  Stir in banana mixture.
3.  Pour batter into prepared pan and bake in preheated oven for 80-90 minutes or until toothpick inserted in center comes out clean.  (It makes a large batch, so it might be helpful to place the baking dish on a sheet pan to catch any overflow).
4.  Remove from oven and place directly into the freezer for 45 minutes.  This will make the cake very moist. 
5.  For frosting, cream the butter and cream cheese until smooth.  Beat in 1 tsp. vanilla.  Add powdered sugar and beat on low speed until combined, then on high speed until frosting is smooth.  Spread on cooled cake.  Sprinkle with chopped walnuts, if desired.