Step 1

Preheat the oven to 350°F and line two baking sheets with parchment paper.

Step 2

Combine the flour, baking soda, baking powder, salt, and cinnamon in a large bowl. In a separate bowl, whisk together the melted coconut oil, sugar, whole egg, egg yolk, and vanilla, whisking vigorously.

Step 3

Stir the wet ingredients into the dry ingredients. Stir in the oats, raisins, and walnuts, if using, folding into a tight batter. Set the dough aside for 20 minutes while the oven preheats. (Note: if your dough seems too wet to become scoop-able, chill it in the fridge for this 20 minutes and it'll firm up).

Step 4

Scoop into 20 tablespoon-sized balls and roll lightly in barely damp hands to make them round. Spread out onto the prepared baking sheets and bake until puffed, golden, and a touch underbaked-looking, 10 to 11 minutes. Let cool on the pans for 5 minutes before transferring to a wire rack to cool completely.