• Preheat the oven to 350°F (180°C). Line a 12-hole muffin tray with a paper liner. Set aside.
• In a small bowl, stir blueberries and cornstarch until they are well coated. Set aside.
• In a large bowl, whisk apple cider vinegar and almond milk. Set aside for a few minutes until it looks curdled.
• In another large mixing bowl, whisk all-purpose gluten-free flour, oat flour, salt, baking soda, and baking powder. Set aside.
• In another large bowl, add the curdled almond milk made before, olive oil, applesauce, coconut sugar, maple syrup, and vanilla extract.
• Combine the dry ingredients with the wet ingredients until the batter is smooth and no lumps of flour can be seen.
• Fold in the coated blueberries and stir until just combined. Don't over-mix the batter to avoid gummy muffins.
• Fill the 12 muffin holes up to 3/4 their level.
• Bake the muffins for 25-35 minutes or until golden brown and a toothpick insert in the middle of one muffin comes out clean.
• Cool down for 5 minutes in the muffin tin, then transfer to a cooling rack to cool completely at room temperature.

Storage

• Store in an airtight container in the fridge for up to 4 days.
• Freeze the muffin for up to 1 month in zip-lock bags and thaw at room temperature the day before.