Preheat your oven to 350°F / Grease your cake tins with butter or coconut oil and line the bottoms with parchment paper rounds.
In the bowl of your stand mixer fitted with a paddle attachment, or a large bowl if mixing by hand, add in your flour, sugar, baking soda, salt and cocoa powder and mix on slow speed just for a few seconds to combine.
In a large bowl, combine all your wet ingredients: oil, buttermilk, eggs, vanilla and red food coloring and mix, using a whisk, making sure it is fully combined.
Add your wet mixture into your stand mixer bowl, and mix on very low speed, pulsing on and off a few times to get it started, preventing the mixture from splattering. Continue to mix on low speed just until combined; alternatively, you can do this by hand. Make sure to not over mix the batter; the batter will be pretty wet.
Evenly distribute your batter into your prepared tins and bake for about 30-35 min, or until the top is set and the cake springs back when slightly pressed with your finger.
Time will vary depending on how many tins and what size tins you use, but once the top is set, and springs back when touched, they are perfect. Remember, they will continue to set in the middle as they cool, so make sure to not over bake them as they might dry out otherwise.
Let your cakes cool in their tins, and once cool enough to handle, you can remove them onto a cooling rack.
Once completely cooled, use a serrated knife to even the tops (saving the shavings for crumbs, if desired) and layer them if you wish to do so.