Grease and line a 2lb loaf tin with non-stick baking paper. Pre-heat the oven to 180ºC.
Pop the flour, baking powder and salt into a large bowl and mix together well.
In another bowl, add the sugar, maple syrup, olive oil, dairy free milk, lemon juice, lemon zest and vanilla essence and stir well to combine.
Pour the wet ingredients into the dry and mix together well, but lightly so you don't lose all the air bubbles created from the lemon juice hitting the raising agents. Quickly stir in the blueberries, pour into the prepared tin
Tap the tin on the worktop then place in the oven for 35 -40 minutes until the top is nicely browned and a toothpick comes out clean. Remove from the oven and leave to cool slightly in the tin.
If you're adding lemon drizzle (really worth it) mix the lemon juice and coconut sugar together in a small bowl. Prick lots of holes in the top of the cake, with a toothpick or fine skewer, then pour spoonfuls of the lemon mixture over the top, letting it soak into the holes. Leave to cool in the tin for 20 minutes then tip out onto a cooling wrack, peel off the baking paper and leave to cool completely.
Scatter fresh berries over the top (if using), and cut into slices to serve.
