Preheat the oven to 350º. Place the butter and chocolate chips in a large glass bowl over a pot of gently boiling water. Whisk together until the butter and chocolate are melted and well combined. Set aside and let cool for five minutes.
In a bowl, whisk together the almond flour, cocoa powder, baking powder and salt. In a separate bowl, whisk together the eggs, sugar and vanilla.
Whisk the cooled chocolate and butter mixture into the egg and sugar mixture. When combined, mix into the dry ingredients. Pour into a buttered 8-by-8-inch baking pan and bake for 25 minutes.