Warm 1 ¾ cup low fat or skim milk and 8 Tablespoons unsalted butter together in the microwave or a small saucepan over medium heat until butter is melted. Allow to cool until just warm.
Whisk together 1 cup whole wheat flourn 1 cup all purpose flour, 1 Tablespoons sugar, 1 ½ teaspoons instant or quick rise yeast, and ½ teaspoons salt in a large bowl. Whisk in the milk and butter mixture slowly.
Stir together 2 large eggs and 1 teaspoon vanilla, then stir this mixture into the batter.
Cover bowl with plastic wrap or a lid and let rise in the fridge for 12-24 hours.
When ready to cook, heat waffle iron. Spray lightly with canola oil if desired. Sprinkle pearl sugar evenly into the waffle iron, if using. Spoon in batter with a ladle, being careful not to over- or under-fill. Sprinkle more pearl sugar on top of the batter.
Cook waffle until steam diminishes and waffles are golden brown and crisp. Serve immediately or allow to cool on a wire rack to freeze. Freeze in an airtight container or freezer bag and reheat in the toaster.
Notes
Pearl sugar can be found in the baking section of a well stocked store.