Preheat your oven to 350°F (180°C) and prepare three 7-inch cake pans with grease and parchment paper.

Mix soy milk with vinegar and let sit for 5 minutes to create a vegan buttermilk.

In a large bowl, whisk oil, sugar, vanilla extract, and citrus zest. Add the curdled soy milk and mix well.

In another bowl, whisk together flour, cornstarch, baking soda, and salt. Combine with the wet mixture gently, folding in floured cranberries if using.

Divide batter among the pans and bake for 20-25 minutes until golden and a toothpick comes out clean.

Allow cakes to cool in pans for 10 minutes, then transfer to a wire rack to cool completely.

For the compote, boil cranberries, water, orange juice, and sugar, then thicken with cornstarch before cooling.

Whip non-dairy cream with powdered sugar and cream stabilizer until stiff peaks form for frosting.

Assemble the cake by layering with frosting and cranberry compote between cakes, then frost the entire cake.