Preheat and Prepare: Preheat your oven to 180°C (350°F). Grease two 8-inch cake pans and set them aside.

Make the Batter: In a mixing bowl, whisk together the flour, sugar, salt, and baking soda. Add the vinegar, oil, vanilla extract, and water, and mix until smooth. Divide the batter evenly into two separate bowls. Stir yellow food coloring into one bowl and red food coloring into the other.

Bake the Cakes: Pour each colored batter into the prepared cake pans. Bake for 25-27 minutes, or until a skewer inserted into the center comes out clean. Remove the cakes from the oven and let them cool completely. Once cooled, carefully slice each cake horizontally to create four thin layers.

Prepare the Frosting: In the bowl of a stand mixer, combine powdered sugar and butter. Beat on low speed until smooth and creamy. Add the vanilla extract, then gradually mix in the heavy whipping cream until fully combined. Divide the frosting into two bowls. Stir red food coloring into one portion, leaving the other plain.

Assemble the Cake: Place one red cake layer on a flat surface and spread a layer of plain frosting on top. Add a yellow cake layer and spread more frosting. Repeat this process, alternating colors, until all layers are stacked. Use the red frosting to cover the top and sides of the cake.

Serve: Let the cake sit for a few minutes to set, then slice and enjoy!