Preheat oven to 350°F. Line a 9” x 7” baking pan with parchment.
In a microwave-safe bowl, combine butter and dark chocolate. Microwave for 30 seconds until melted; stir until smooth.
In a bowl, combine almond flour, Splenda Stevia Sweetener, cocoa powder, and baking powder.
In a bowl using an electric mixer, beat eggs until frothy. Add chocolate mixture and vanilla extract and mix to blend. Slowly add dry ingredients, mixing on low speed until smooth.
Transfer batter to prepared pan and bake for 15–20 minutes, until brownies are set but still slightly moist to the touch. Cool before cutting into squares.