- Preheat oven to 325°.
- Grease a 8" square baking dish or a 9x11" baking dish. Dust with cocoa.
- Sift flour, cornstarch, baking powder, cocoa, cinnamon, and salt into a large bowl.
- Add sugar to the bowl and stir.
- Add eggs and stir with a spoon or spatula until combined.
- Stir in melted coconut oil and softened butter until blended.
- Stir in nuts.
- Spread the batter into your prepared pan.
- Bake about 25 minutes or longer, until a knife or toothpick inserted comes out clean.