In a large mixing bowl, combine the oats, nut butter, honey or maple syrup, and cocoa powder. Stir with a strong spatula or spoon until the mixture is well combined and sticky, about 2-3 minutes.

Using a cookie scoop or tablespoon, portion out the dough onto a lined baking sheet. Leave space between each scoop for spreading. Press each ball gently to flatten slightly.

Preheat your oven to 350°F (175°C). Prepare any optional add-ins by chopping them or measuring them out.

Place the baking sheet in the preheated oven and bake for 10-12 minutes. Remove when the edges turn crisp and the centers are slightly soft.

Let the cookies cool on the sheet for 5 minutes, then transfer them to a wire rack to cool completely.

Enjoy fresh with a glass of milk or store in an airtight container for up to a week.