Preheat the oven to 350°F and line an 8x8-inch square cake pan (or 9-inch round pan - see notes) with parchment paper so that the parchment stick up over the edge of the pan by a couple of inches for easy removal after baking.
Whisk together the 1½ cups all-purpose flour, 1 cup granulated sugar, 1 teaspoon baking soda, and ½ teaspoon salt in a mixing bowl.
Create three wells in the flour mixture and add the ⅓ cup vegetable oil or canola oil to one well, 2 teaspoons vanilla extract to another, and 1 teaspoon white vinegar to another.
Pour the 1 cup water all over the top of the mixture and then whisk together.
Pour the batter into the prepared baking pan and bake for 22 to 26 minutes or until a cake tester comes clean from the center of the cake.
Let the cake cool in the pan for 10 minutes before removing it by lifting the parchment paper and transferring it to a wire rack.
Once cooled, frosting with desired frosting or serve plain with a dusting of powdered sugar, whipped cream, and berries.