There are plenty of ways to mix up this recipe. Here are some suggestions:
For regular waffles: just omit the banana, and increase the oil to ¼ cup. (I like to use 1 tsp. sugar if I'm using a banana, and 2 tsp. sugar if not -- but that's totally personal preference.)
To banana bread waffles or regular waffles, try adding a pinch of cinnamon and nutmeg, or other spices like chinese five spice or ginger.
Swap the banana for pumpkin puree and a dash of pumpkin pie spices.
Make regular waffles, but stir in a spoonful of cocoa powder to the dry ingredients, and top with chocolate chips. (For add-ins like nuts and chocolate, I prefer to use them as a topping rather than adding them directly to the batter, so I don't have to worry about them burning to the waffle iron.)
For quick and easy waffles, I like to make a mix out of the dry ingredients. Just whisk together 5 or 6 times the dry ingredients in a bowl, store in an airtight container, and when you want to make waffles, scoop 1 cup of mix and follow the recipe as written. You can also make smaller or larger batches of waffles easily, just be sure to adjust the wet ingredients accordingly (i.e., for half a cup of mix, halve the wet ingredients).
Recipe adapted from
these waffles on foodnetwork.com