Preheat oven to 325 degrees. Grease a 12 x 9 or 13 x 9 baking dish with coconut oil or butter.
To make the topping, place the walnuts, coconut oil or butter, sugar and cinnamon in the food processor fitted with a metal blade and pulse until combined and the texture resembles a crumb topping. Remove from food processor and set aside.
In the same food processor (no need to clean it) place the beans, eggs, stevia, vanilla coconut oil and honey and puree until smooth.
Then add the coconut flour, salt, baking soda and baking powder to the white bean mixture and process until smooth. Pour into the greased pan.
Spread the topping over the top of the batter and use a fork to swirl into the batter, then pat down to set.
Bake for 35 minutes or until a toothpick inserted in the center comes out clean. Allow to cool before serving. Store leftovers in the refrigerator where it will stay good for up to a week.