Preheat the oven to 350 degrees F and grease a 9x13 inch cake pan.

Combine the soy milk and vinegar in a measuring cup or bowl, stir and set aside for a few minute to curdle.

In a large bowl, whisk together the flour, cornstarch, sugar, baking powder, baking soda and salt.

Now pour in the milk/vinegar, oil and vanilla. Whisk until combined and there are no large lumps left in the batter.

Pour the batter into the cake pan, transfer to the oven and bake for 20-25 minutes, until a toothpick inserted in the center comes out clean. Remove from oven and let the cake cool for about 15 minutes. The cake should still be warm when you pour the milk over it; it will absorb better.

Scoop/pour the full fat coconut milk into a large microwave safe bowl. Heat for 1 minute, until warm and there are no more hard white portions.

Add the sweetened condensed coconut milk and oat milk to the bowl with the coconut milk and whisk well.

Use a fork to poke holes all over the top of the cake, all the way down to the bottom of the pan.

Slowly pour the milk mixture over the cake.

Refrigerate the cake for at least an hour to let it soak up the milk.

Prepare whipped topping. Remove the cake from the refrigerator and smooth whipped cream all over the cake.

Sprinkle with cinnamon and decorate with fresh sliced strawberries, if desired. Store vegan tres leches cake in the refrigerator for 3-5 days, covered.