01 - Preheat oven to 350°F (175°C). Line a 12-cup muffin pan with paper liners or lightly grease each cavity.
02 - In a large mixing bowl, stir together rolled oats, almond flour, cocoa powder, sea salt, and baking powder until evenly blended.
03 - In a medium bowl, whisk melted coconut oil, maple syrup, brown sugar, eggs, and vanilla extract until smooth and fully blended.
04 - Pour wet mixture over dry ingredients. Gently mix until incorporated; do not overmix.
05 - Add dark chocolate chips and optional nuts. Fold just until evenly dispersed.
06 - Spoon mixture evenly into prepared muffin cups, filling each approximately three-quarters full.
07 - Place pan in the oven and bake for 18 to 20 minutes, until centers are set and a toothpick inserted comes out mostly clean with some melted chocolate.
08 - Let oatmeal cups cool in the pan for 10 minutes, then transfer to a wire rack to cool completely before serving.