Blackberry Lavender Jam:
Cake Batter:
Frosting
Cake Batter:Preheat oven to 180°C/356°F. Line the bottom of a 10-inch springform pan with parchment paper. Grease the sides of the pan and the parchment paper with a little vegan butter. In a small bowl, combine the non-dairy milk and apple cider vinegar. Set aside to curdle. In a large bowl, beat the vegan butter and sugar for 2–3 minutes until light and creamy. Add the vanilla extract and beat again. Pour in the buttermilk (mixture may look separated). Add the flour, cornstarch, salt, baking powder, and baking soda. Fold until no visible flour remains.