• Preheat oven to 350 degrees F.
• Line an 8x8 inch baking pan with parchment paper (check out this easy tutorial).
• Lightly spray with coconut oil or grease with butter.

For the brownie batter

• Place the butter and chocolate together in a microwave-safe bowl and heat in the microwave in 30-second increments stirring in between until smooth.
• Stir in the vanilla extract.
• Add the almond flour, powdered sweetener, cocoa powder, sea salt, eggs, white vinegar, and food coloring.
• Stir together until well combined.
• Transfer 3/4 of the batter to the lined pan and set aside the other 1/4 of the mixture.

For the cheesecake mixture

• In a medium bowl, beat the cream cheese and powdered sweetener together on medium speed, until fluffy.
• Beat in the eggs, one at a time.
• Beat in the white vinegar and vanilla extract.

To assemble

• Mix 1/4 cup of the cheesecake batter into the reserved brownie batter and mix until smooth.
• Carefully fold the reserved brownie batter into the cheesecake filling mixture with a rubber spatula. Making sure not to over-mix - you want to leave swirls in the mixture. Use a skewer or toothpick to swirl if needed.
• Pour the mixture into the pan on top of the brownie batter.
• Bake for about 35-40 minutes, until the cheesecake layer is almost set, but still slightly jiggly.
• Cool completely before moving or cutting.