Turn on waffle maker and let it heat up for at least 5 minutes.

Mix the batter ingredients in a measuring cup or another cup you can easily pour from. Once waffle maker is heated, spray with cooking spray. Pour half the batter in the waffle maker, close the maker, and flip it (if your maker is one that flips (I recommend this waffle maker). Put the timer on for 4 minutes. Repeat with remaining batter when the first waffle is done.

While waffles are cooking, microwave blueberries for 1 to 1.5 minutes. Mash the blueberries with a fork and stir in maple syrup. Let the mixture sit for a few minutes to thicken.

Once waffles are done, pour the syrup over them and top with more crushed walnuts if desired.