Banana Cake with Cream Cheese Frosting

I just made this recipe last night, and it turned out great (moist and delicious) , I definitely making this again, I mad a few changes to the recipe adding Cinnamon, less sugar, and using milk + lemon juice rather than buttermilk.

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Ingredients:
1 1/2 cups ripe, mashed bananas (approximatively 3 bananas)
2 teaspoon lemon juice
3 cups flour
1 1/2 teaspoon baking soda (heaping spoonfuls)
1/4 teaspoon salt
3/4 cup softened butter (3 sticks butter)
2 cups sugar *I probably only added 1 1/2 cups 
3 large eggs
2 teaspoon vanilla extract
1 1/2 cups buttermilk
1 cup chopped toasted walnuts (optional)

Cream Cheese frosting:
1/2 cups of softened butter (1 stick)
1 - 8 oz package of cream cheese, softened
1 teaspoon vanilla extract
3 1/2 cups confectioner (powdered) sugar

Directions:
1. Preheat oven to 275 degrees  *Since I've notice my oven does not always heat properly I actually preheated to 300 degrees and then when I put the cake in turned it down to 275
2. Grease and flour a 9x13" pan
3. In a small bowl, mash up banana & lemon; set aside
4. In a medium bowl, mix flour, baking soda and salt; set aside *I added about a tablespoon of Cinnamon
5. In a large bowl, cream butter & sugar until light and fluffy. *this is where I love my KA standmixer
6. Beat in eggs, one at a time, then stir in vanilla extract
7. Add in approximatively on cup of flour mixture, mixing alternately with buttermilk (approx. 1/2 cup) until all flour mixture and buttermilk is added.
8. Stir in banana mixture.
9. Pour batter into pan, bake for approximatively one hour or until toothpick inserted in the center comes out clean.
10. Remove from oven and place directly into freezer for 45 minutes, this will make the cake very moist. *For you cold weather ladies, I stuck my cake outside with the snow (as long as it wasn't currently snowing or raining)
11. While cake is chilling prepare the frosting, cream butter and cream cheese until smooth
12. Beat in vanilla extract.
13. Add in about half of powdered sugar, beat at low speed until combined, then beat at high speed until smooth.
14. Taste frosting, continue adding powdered sugar until frosting reaches your desired sweetness *I never add the total 3 1/2 cups of adding powdered sugar 
15. Spread frosting over cooled cake
16. Sprinkle walnuts over frosting