Preheat oven to 375 degrees F. Line 12-cup muffin tray with paper or reusable liners.

In small bowl, mix together flax and water. Let sit 10 minutes to form gel.

In medium bowl, combine gluten-free flour mix ingredients.

In separate bowl, stir together milk, apple cider vinegar and baking soda.

In large bowl, mix together coconut oil, maple syrup, coconut sugar and SunButter. Add flax mixture and whisk, then stir in milk mixture. Lastly, add flour mix and salt and combine well.

Gently stir in blueberries and chia seeds.

Pour batter evenly among liners and bake 24 minutes or until golden brown. (Note: Toothpick inserted in center should come out clean.)

Let cool in pan 15 minutes.