In a bowl, mix together the cacao powder, flaxseed meal, baking soda and salt.
In a separate bowl, whisk the coconut milk, egg, vanilla, honey and sunflower seed butter.
Gently mix wet and dry ingredients to form a batter.
Fold the chocolate chips into the batter and pour it evenly across the bottom of a 9-inch square silicone pan. If you are using an aluminum or non-stick pan, you can line it with parchment paper or grease it with coconut oil.
Bake until a toothpick inserted into the center comes out clean, about 15-20 minutes. Set pan over a wire rack to cool then cut into squares.