In a large bowl, mix the sugar and coconut oil until creamy. Beat in egg. In a separate bowl, mix flour, baking powder, salt substitute and cinnamon. Add greek yogurt, milk and vanilla extract to the egg and sugar mixture. Slowly fold in the liquid mixture into the dry mixture until moist. Fold in the blueberries and spoon into a greased muffin pan. Sprinkle turbinado sugar on each muffin.