First turn the oven to 120°C/fan 100°C/gas ½. Blitz the oats in a food processor until you have a scruffy oat flour. Add the oats to a bowl with the pecans and throw in the baking powder and salt.
Mix the mashed banana with the milk (you can do this by blitzing them together in the food processor, if you like). Beat the banana mixture into the flour and leave the batter to sit for a few minutes.
Heat a non-stick pan on a medium heat, then add the banana slices and fry on both sides in the dry pan until brown and caramelised. Keep warm in the oven.
Put the pan back on a medium heat and add a little coconut oil or butter. Drop in a healthy tablespoonful of batter for each pancake. Once the sides are cooked and bubbles have risen to the top, scatter over a handful of blueberries and flip the pancake over. Cook for another couple of minutes on the other side. The pancakes will stay a little moist in the middle because of the banana, so don’t worry. Keep them warm in the oven while you cook the rest.
Serve the pancakes piled with the banana slices. Add some crumbled pecans and a squeeze of lime, and, if you like, a little touch of honey, agave or maple syrup.