Blend the ground flax-seed & the water in small cup and set aside for 15 minutes.
Sieve the flour, the cocoa powder, the bicarbonate of soda, the baking powder and the pinch of salt into a bowl, stirring & mixing well.
Pour the oat milk, the oil, the vanilla extract, the flax-seed eggs and mashed banana in a separate bowl and mix them. As soon the mixture has the silky texture, add the flour mixture and the chopped bar of chocolate.
Take a muffin baking form, filling with paper cups, and using ice-cream scoop to fill up with the muffin batter one by one.
Bake the muffins in 180C° preheated oven for 20-25 minutes.
