Preheat oven to 350°F. Generously spray a muffin tin with cooking spray.

In a large bowl, whisk together 3 cups almond flour (300 g), 4 tablespoons coconut flour (firmly packed, 32 g), 1 tablespoon baking powder, 1 teaspoon baking soda, and 1 teaspoon salt.

In a separate bowl, whisk together 3/4 cup monk fruit, 6 tablespoons melted ghee, 6 tablespoons full-fat canned coconut milk, 3 large room-temperature eggs, and 1 tablespoon vanilla extract until smooth.

Pour the wet ingredients into the dry ingredients and stir until just combined. The mixture will be very thick.

Fold in 1/2 cup + 1 tablespoon Stevia-sweetened chocolate chips and 1/4 cup diced black walnuts.

Let the batter rest for 5 minutes to allow the coconut flour to absorb the moisture. Stir once after resting if needed.

Fill each muffin cup about two-thirds full (an ice cream scoop works well for even portions).

Bake at 350°F for 25–27 minutes, or until the tops are golden brown and a toothpick inserted into the center comes out clean or with a few moist crumbs.

Remove the pan from the oven and let the muffins cool in the pan for 10–15 minutes. Run a knife around the sides of each muffin to loosen them and remove them from the pan. Transfer to a rack and cool completely before serving or storing.