Preheat your waffle iron to a medium-high setting. Grease lightly if necessary.

In a large bowl, whisk together flour, sugar, baking powder, baking soda, and salt.

In a separate bowl, whisk the eggs until frothy. Then whisk in the buttermilk, oil (or melted butter), and vanilla extract.

Pour the wet ingredients into the dry ingredients and mix gently until just combined. Do not overmix.

Divide the batter evenly between two separate bowls.

To one bowl, add the cocoa powder, red gel food coloring, and white vinegar. Fold gently until fully incorporated and the batter is a uniform red color.

Using two spoons, place alternating dollops of the red velvet and vanilla batters onto the center of the hot waffle iron.

Use a knife or skewer to gently swirl the batters together once or twice. Close the lid and cook for 4-6 minutes, or until steaming stops and waffles are crisp.

Carefully remove the waffle and serve immediately with desired toppings like cream cheese glaze, powdered sugar, or maple syrup.