Spray a 12 capacity muffin pan with non-stick spray and set aside.
In a bowl whisk together whole wheat flour, all purpose flour and oats.
Add baking soda, baking powder, salt and all spice mix (optional). Mix till everything is well combined. Set aside.
In another bowl, whisk together oil, egg, mashed banana and yogurt. Whisk till well combined.
Add brown sugar, vanilla extract and mix well.
Start adding the dry ingredients into the wet in parts, mixing after each addition.
Mix till dry ingredients are just combined, do not over-mix.
Stir in the mini semi-sweet chocolate chips. You can also add nuts here.
Divide the batter equally into 11 muffins pans, filling all the way to the top.
Bake at 400 F degrees for 10-13 minutes or till a toothpick inserted in the center comes out clean. I baked mine for around 13 minutes and I do think I over-baked them a little. They were super soft and moist but a bit too brown for my liking. So keep an eye on them after 10 minutes.
Transfer the muffins onto a wire rack to cool completely.