Preheat the oven to 180C/350F/Gas Mark 4 and line muffin tin with 10-12 paper cases.
In a large bowl mix together flour(s), ground almonds, baking powder, baking soda, salt (if using), sugar and lemon zest.
Add fresh blueberries and mix them in gently so that they're nicely coated in dry ingredients (feel free to save some to put on the top of the muffins).
In a jug mix together soya milk, apple cider vinegar, oil and vanilla or almond extract (if using).
Pour the wet ingredients into the dry ones and mix in gently (using folding motion) to incorporate. Be careful not to overmix your batter.
Next, divide muffin batter in between prepared muffin cases and sprinkle generously with some demerara sugar to create crunchy topping.
Bake in preheated oven for approximately 25 minutes until risen and spring back when touched and skewer inserted into centre comes out clean (no raw batter on it but some blueberry juice is fine).
Let the muffins cool in the tin for 5-10 minutes before taking them out onto the wire rack to cool completely.
Enjoy!