• Preheat the oven to 350°F (180°C). Line a 12-muffin hole pan with paper cases and use an oil spray to grease the cases. Set aside.
• Peel and mash the bananas, and pack them in a measuring cup to measure 1 cup.
• In a large bowl add mashed bananas, egg, melted coconut oil, and vanilla, and whisk to combine. Set aside.
• In another bowl, stir flour, baking powder, baking soda, and sugar.
• Make a well in the center of the flour, fold in liquid ingredients and stir with a silicone spatula halfway, then fold in berries and keep stirring a few more times to incorporate. Don't over-mix the batter, stir until no more lump of flour can be seen not more. If you over-stir the batter, the muffins come out dense or sometimes gummy.
• The batter should be thick but not overly dry, if dry add 1-2 tablespoons extra milk or water.
• Fill the muffin cases up to 3/4 level.
• Bake the muffins on the center rack of the oven at 350°F (180°C) until a pick inserted in the center of the muffin comes out clean - about 25-35 minutes.
• Cool on a wire rack for one hour.

Storage

• Store in the fridge in an airtight box for up to 4 days or freeze in a sealed box for up to 4 months.