Prep: Preheat oven to 350 and line an 8x8 baking pan with parchment paper.
Cream: Add melted butter, brown sugar, molasses, aquafaba, and vanilla to a mixing bowl and cream together.
Mix: In another mixing bowl, add in flour, baking powder, baking soda, baking powder, spices and salt. Whisk to combine
Combine: Add flour mixture to the butter mixture and fold to combine. Don't over-mix.
Bake: Spread batter evenly and bake for 20-30 (or until golden). Careful not to overbake.
Icing: Make icing by adding butter, cream cheese, vanilla and powdered sugar to a mixing bowl. Use a handheld mixer to whip.
Cool & cut: Let the blondies cool completely before icing and slicing for clean edges.