In a small bowl, mix flaxseed with 5 tsp of boiling hot water. Stir and set aside. Next, cover the apple cubes with ½ tsp of plain gluten-free flour in a small bowl.
In a large bowl, sift and mix the rest of the dry ingredients (except hemp seed hearts) and separately in a large cup or mug, mix together all your wet ingredients.
Slowly pour your wet mixture and flaxseed mixture over your dry mixture. Stir until no more flour can be seen, add apples and stir again.
Pour your mixture into lined muffin tray about 4/5 full, sprinkling hemp seed hearts on top of each.
Bake at 180°C for 30-35 minutes until a wooden skewer inserted in the middle comes out clean.