Make your flax egg by combining the ground flaxseed with 2.5 tbsp of water and set aside for 5-10 minutes to turn into a gel consistency.
While the flax egg is coming together, mix together flour, baking powder, granulated sugar, and salt. Add the coconut oil to the dry ingredients and mix together until the consistency resembles big crumbs.
Add in the coconut milk, flax eggs, and vanilla extract, and mix until fully combined. Then add in lemon zest if using, and blueberries, and gently combine until they are evenly distributed throughout.
Transfer the dough onto a parchment paper lined plate or pan and shape into a large disc, around 8 inches across and 1 inch high. Move to the fridge to chill for an hour.
During this time, preheat the oven to 400°F. Once the dough is fully chilled, remove from the fridge and slice into 8 equal sized wedges.
Move wednges onto a parchment paper lined pan. If you chilled them in the fridge on a pan, DO NOT use this same pan in the oven, as it is starting from too cold to cook the bottom of the scones the way they need to be cooked.
Bake at 400°F for 25-28 minutes, until golden brown on top. If you are using the glaze, combine powdered sugar with lemon juice or non-dairy milk, and spoon over the tops of the scones.
Eat and enjoy!