Preheat the oven to 190°C (375°F) and line a 10-cup muffin tin (if using a 12-cup tin, simply line 10 cups instead).
Add the rolled oats to a food processor or dry-ingredient safe blender and mixing until they turn into a coarse flour, then set aside.
1 cup rolled oats
If using whole almonds, process them in the same way until they too are flour. If you are using almond flour instead, skip this step.
Add the ground oats, 1 cup of almond flour, the buckwheat, arrowroot, sugar, baking powder, soda, salt, and spices in a bowl. Stir to combine.
1 cup almond flour, ⅔ cup buckwheat flour, 2 tablespoons arrowroot powder, ⅓ cup coconut sugar, ¾ teaspoon baking powder, ½ teaspoon baking soda, ½ teaspoon cinnamon, ¼ teaspoon ground nutmeg, ½ teaspoon sea salt
In a separate bowl combine the banana, oil, lemon juice, milk and vanilla, stirring well. Combine the wet ingredients to the dry and mix just until combined. Lastly, stir in the chocolate.
1 ½ cups mashed banana, ⅓ cup avocado or coconut oil, 1 teaspoon lemon juice or apple cider vinegar, ¼ cup non-dairy milk, 1 teaspoon vanilla extract, ¾ - 1 cup dark chocolate chips
Divide batter amongst 10 lined muffin cups and sprinkle the tops with a little bit of almond flour if desired. Bake for about 25 minutes or until the tops spring back when lightly touched.
Cool the muffins on a wire rack. Store in a sealed container at room temperature for up to three days or freeze up to three months.