Preheat oven to 350 degrees F. Line an 8x8 baking pan with parchment paper and lightly spray with cooking oil. Set aside.
In a large mixing bowl beat the softened butter, and granular sweetener with an electric mixer until creamy and well incorporated.
Beat the eggs into the sugar mixture until completely combined.
In another bowl combine the almond flour, coconut flour, baking powder and salt.
Spoon the flour mixture into the sugar mixture, beating with an electric mixer until smooth.
Stir in the lemon zest and lemon juice.
Spoon batter into the prepared baking pan. Bake 22-26 minutes or until a toothpick inserted in the center comes out clean.
Allow the blondies to cool completely before frosting. To make the frosting: Combine the sweetener, cream cheese, lemon juice, lemon zest, vanilla and 1 tablespoon of the milk or heavy cream in a food processor or beat with an electric mixture until smooth and creamy. Add 1 tablespoon additional liquid if needed until it reaches your desired consistency.
Notes
See notes in post for tips.Net carbs are 2.2 g per bar