Preheat oven to 175ºC. Prepare two 23 cm cake pans by greasing, flouring, and lining bottoms with parchment paper. This is a moist cake, do all three to make sure it doesn't stick.
In a large bowl, whisk together flour, sugar, baking powder, baking soda, and salt.
In a separate bowl, whisk the eggs, then whisk in the vegetable oil, buttermilk, and vanilla. Pour into the flour mixture and gently fold together until no dry patches remain. Don't over-mix.
Divide batter between prepared cake pans and bake about 35 minutes, rotating pans once.
Cakes are done when the centers feel springy (not squishy) when gently pressed. If in doubt, pull out your thermometer - the internal temperature should be 93-96ºC.
Let cakes cool 5 minutes in pans before transferring to wire racks to cool completely.