In a medium bowl combine the crumble topping ingredients and stir together until a crumbly mixture forms. Set aside.
60 g plain white flour, 70 g granulated sugar, 40 g vegan butter
To Make the Cake
Preheat the oven to 170 °C. Grease and line a 20x20cm square cake tin.
In a medium bowl, combine the caster sugar and lemon zest. Rub together with your fingertips until fragrant.
220 g caster sugar, Zest of two lemons
Add the sunflower oil, vegan yoghurt, soy milk, lemon juice and lemon extract to the bowl and whisk until smooth. Set aside.
90 ml sunflower oil, 150 g vegan yoghurt, 100 ml plant milk, 50 ml lemon juice, ½ teaspoon lemon extract
In a medium bowl sieve together the plain white flour, baking powder, bicarbonate of soda, fine sea salt and corn starch. Mix to combine.
250 g cake flour, 1 ½ teaspoon baking powder, ½ teaspoon bicarbonate of soda, ¼ teaspoon fine sea salt, 1 tablespoon corn starch
Add the combined wet ingredients and beat again until just smooth. Don’t over mix.
Transfer the batter to the prepared cake tin. Top with the blueberries and sprinkle with the crumble topping. Bake for 35-40 mins or until a cake tester comes out clean. Remove from the oven and allow to cool fully before slicing and serving.