Preheat oven to 375 degrees F. Prepare 2 round 8 or 9-inch cake pans or 1 9x13-inch cake pan by greasing and lightly coating with flour or cocoa powder. Or prepare 24 cupcakes liners in a cupcake tin.
Sift or whisk together the flour, sugar, cocoa powder, baking soda, and salt in a large bowl.
Combine the vegetable oil, cold espresso or coffee, and vanilla.
Add the wet mixture to the dry mixture and blend until smooth. (1-2 minutes by hand)
Add the vinegar and stir quickly to combine until the vinegar is evenly distributed. Don't over-blend it.
Pour the batter into the pan right after blending.
Bake for 25-30 minutes for 8 or 9-inch pans, 30-35 minutes for 9 x 13-inch pans, or 20-25 minutes for cupcakes. Check for doneness with a toothpick. Cool on a wire rack.
If making cupcakes, pop the cupcakes in liners out of tins after 3-5 minutes to prevent liners from peeling away from the cupcakes.
Frost as desired. Try our better buttercream frosting. Link in notes.