Place the orange juice, zest, sugar, oil, vinegar and vanilla in a large bowl or in the bowl of a stand mixer. Use a whisk or the whisk attachment of the stand mixer to mix for one minute or until everything appears to be well-mixed.
Add the baking soda, salt and flour to the bowl and mix. Scrape down the sides of the pan after 20 seconds of mixing and mix for 20 seconds more, but no longer.
Spray two 8- or 9-inch cake pans with cooking spray or oil. Preferably line the bottom with parchment paper, or, if you don't have this, flour the pans. Divide the cake batter equally between the two pans.
Bake the cakes in a 350-degree oven for 30-35 minutes until a toothpick inserted in the center comes out clean.
Cool on a rack for 10 minutes, then slide a thin knife around the edges of each cake
Gently flip each cake onto a plate, slide onto a rack, and continue cooling before you frost.