Preheat the oven to 350°F. Grease a 9x13 pan.
Mix flour, baking soda, cinnamon and salt in a bowl and set aside.
Cream butter and sugar with hand mixer until fluffy.
Add eggs, milk, mashed banana, & lemon juice. Mix well.
Stir the flour mixture and pecans into the wet mixture.
Spread into the prepared pan and bake for 20 to 25 minutes or until a toothpick comes out clean. Cool completely.
While the bars are cooling, beat cream cheese and butter with a hand mixer until fluffy. Mix in vanilla and a pinch of salt.
Add powdered sugar, a bit at a time, until incorporated. Spread over the banana bars and serve.
