Preheat the oven to 350ºF.

Grease an 8×8-inch baking dish with butter.

In a large bowl, whisk together the almond flour, cocoa powder, baking soda and baking powder.

In a separate bowl, whisk together the melted butter, eggs, honey and sunflower seed or almond butter.

Pour the wet mixture into the dry ingredients and stir to combine thoroughly.

Fold in the chocolate and walnuts.

Pour the batter into the greased baking dish and spread it out evenly.

Bake for about 25 minutes until the brownies pull away from the edge of the pan and a toothpick inserted into the center comes out clean. (The center will still be slightly soft.)

Cool completely.

Cut into 16 bars.

Store in an airtight container at room temperature for up to 3 days or freeze for longer storage.