Step 1: Preheat your oven to 350°F (175°C).
Step 2: Grease and flour your two 9-inch round cake pans.
Step 3: In a large mixing bowl, whisk together the all-purpose flour, sugar, baking soda, and salt until well combined.
Step 4: In another bowl, mix together the vanilla extract, vinegar, vegetable oil, and water until smoothly blended.
Step 5: Gradually add the wet mixture to the dry ingredients, stirring gently until just combined.
Step 6: Fold in the rainbow sprinkles gently into the batter.
Step 7: Divide the batter evenly between the prepared cake pans and bake for 30-35 minutes.
Step 8: Let the cakes cool in the pans for about 10 minutes, then transfer to a cooling rack.
Step 9: Once cool, frost the top of one layer, place the second layer on top, and frost the top and sides.
