Preheat & Prep Pans: Preheat oven to 325°F. Butter two 9 inch round cake pans. Line bottoms with parchment paper, butter the paper, and dust pans with flour.

Dry Ingredients: In a medium bowl, whisk flour, baking soda, and salt for 30 seconds. Set aside.

Mash Bananas: In a small bowl, mash bananas with lemon juice. Set aside.

Cream Butter & Sugars: In a stand mixer with paddle attachment, beat softened butter, 2 Tbsp vegetable oil, granulated sugar, and brown sugar on medium high until pale and fluffy (3-4 minutes).

Add Wet Ingredients: Stir in remaining 2 Tbsp oil. Add eggs one at a time, beating well after each. Mix in vanilla and mashed bananas until just combined.

Combine Dry & Wet: With mixer on low, add flour mixture in three additions, alternating with buttermilk, beginning and ending with flour. Mix just until combined after each addition; do not overmix.

Bake: Divide batter evenly between prepared pans. Bake for 45-50 minutes, until a toothpick inserted in the center comes out clean.

Cool: Cool in pans on a wire rack for 15-20 minutes. Then invert onto rack, remove parchment, and cool completely.

Make Frosting: In a stand mixer with whisk attachment, whip heavy cream to stiff peaks. Transfer to a separate bowl. Switch to paddle attachment. Beat cream cheese and butter on medium high until smooth and fluffy (about 2 minutes). Add powdered sugar and vanilla; beat on medium for 2 minutes.

Fold: Gently fold half the whipped cream into the cream cheese mixture with a rubber spatula. Fold in the remaining cream until no streaks remain.

Frost & Serve: Place one cooled cake layer on a plate. Spread with about 1 cup of frosting. Top with second layer. Frost the top and sides. Refrigerate for at least 30 minutes to set. Let sit at room temperature 10-20 minutes before serving.