Preheat your oven to 350°F (175°C). Lightly grease and flour a 9x13 inch baking pan, or line with parchment paper.

In a large mixing bowl, whisk together the sifted all-purpose flour, granulated sugar, baking powder, baking soda, and salt until well combined.

In a separate medium bowl, combine the unsweetened plain plant milk, neutral oil, and vanilla extract.

Pour the wet ingredients into the dry ingredients. Mix with a spatula until just combined. Do not overmix; a few lumps are okay.

Add the apple cider vinegar to the batter and stir quickly to activate. The batter may become slightly frothy.

Pour the batter into the prepared baking pan and spread evenly.

Bake for 28-32 minutes, or until a toothpick inserted into the center comes out clean.

Remove the cake from the oven and let it cool in the pan on a wire rack for at least 30 minutes. While still warm but not hot, use a fork or skewer to poke holes all over the top surface of the cake. These holes will help the milk mixture absorb better.

In a medium saucepan, combine the full-fat coconut milk, unsweetened plain plant milk, sweetened condensed coconut milk, and granulated sugar.

Heat over medium heat, stirring occasionally, until the sugar has dissolved completely and the mixture is warm (do not boil).

Remove from heat and stir in the vanilla extract. Let the mixture cool down to room temperature.

Once the cake is cooled and poked, slowly and evenly pour the cooled tres leches mixture over the entire surface of the cake. Pour slowly to allow the cake to absorb the liquid.

Cover the pan with plastic wrap and refrigerate for at least 4 hours, or preferably overnight, to allow the cake to fully absorb the milks and chill completely.

The next day (or after sufficient chilling), carefully open the chilled cans of full-fat coconut cream without shaking them. Scoop out only the thick, solid coconut cream from the top, leaving the liquid behind (you can save the liquid for smoothies).

Place the solid coconut cream in a large, very cold mixing bowl (you can chill the bowl beforehand for better results).

Using an electric mixer, beat the coconut cream on high speed for 2-3 minutes until it becomes light and fluffy, resembling whipped cream.

Gradually add the sifted powdered sugar and vanilla extract, continuing to beat until stiff peaks form.

Spread the vegan whipped topping evenly over the chilled tres leches cake.

Optionally, garnish with fresh berries and a sprinkle of cinnamon or cocoa powder before serving.

Slice and serve immediately. Store any leftovers in the refrigerator.