01 - In a large bowl, whisk together flour, sugar, baking powder, baking soda, and salt until evenly distributed.
02 - In a separate bowl, whisk together buttermilk, eggs, melted butter, and vanilla extract until smooth and well combined.
03 - Gently fold the wet mixture into the dry ingredients just until combined. Be careful not to overmix to maintain tender texture.
04 - Divide the batter evenly between two bowls. To one bowl, add cocoa powder and red food coloring; stir until thoroughly blended to create the red velvet batter. Leave the remaining batter plain for vanilla contrast.
05 - Preheat waffle iron according to manufacturer instructions. Lightly grease the surface with oil or nonstick cooking spray.
06 - For each waffle, spoon alternating portions of red velvet and vanilla batters onto the center of the hot iron. Use a chopstick or butter knife to gently swirl the batters together, creating a marbled effect.
07 - Close the lid and cook until waffles are golden brown, crisp on the outside, and completely cooked through, approximately 3 to 5 minutes per batch.
08 - Serve immediately while warm. Accompany with cream cheese glaze, pure maple syrup, or fresh seasonal fruit as desired.