Preheat your oven to 350F and spray a 8-inch square pan with nonstick cooking spray.
In the pan, mix the first 4 dry ingredients (flour, sugar, baking soda, and salt).
Make three little holes in the dry mix – two small ones and one slightly larger.
Pour vinegar into one of the small holes, vanilla extract into the other small hole, and canola oil into the larger hole.
Pour water over everything and mix until it becomes smooth.
Put the pan in the middle of the oven and bake for 35 minutes. Check with a toothpick to make sure it comes out clean.
Let it cool completely before frosting/glaze.