In the morning, start by preheating your waffle iron. Peek at your sponge and see how much it grew! (Older kids love this part.)
Beat together the butter and eggs in a small bowl. Stir into the overnight sponge.
Add the salt, baking soda and optional ingredients if using, and stir to combine. You’ll notice the batter start to produce bubbles – this is how you know it’s ready!
Spray cooking oil on your preheated waffle iron and pour batter onto the plate. Close the lid and bake according to manufacturer's recommendations.
When waffles are done, remove with silicone tongs and serve immediately, or place on cooling rack, to guarantee crispness. Tip: Place a cooling rack on a baking sheet in a warm oven to hold your waffles as you cook the remainder. This will allow air to circulate around the waffles, preventing them from becoming soggy on the bottom.Tip: To freeze, allow to cool completely on cooling rack, then stack and place in freezer bags. Parchment paper in between waffles is optional, but not necessary. Reheat in microwave or toaster.