Preheat your oven to 350°F (175°C).
Prepare an 8x8-inch baking pan by greasing it or lining it with parchment paper.
In a large mixing bowl, combine almond flour, cocoa powder, erythritol, salt, and baking powder.
In another bowl, whisk together melted butter, eggs, and vanilla extract until smooth.
Pour the wet mixture into the dry ingredients and mix until just combined. Fold in chocolate chips if using.
Pour the batter into the prepared baking dish and spread evenly.
Bake in the preheated oven for 20-25 minutes, checking for doneness with a toothpick.
Let the brownies cool in the pan for at least 10 minutes before cutting into squares.