In a small mixing bowl, combine 1/2 cup of peanut butter, 1 egg, 1/4 cup of unsweetened cocoa powder, a pinch of salt, and 2 tablespoons of monk fruit sweetener. Stir until smooth, ensuring all elements are fully incorporated. If the mixture appears too thick, gradually add water, one tablespoon at a time, until you achieve a thick yet pourable consistency.

Set up your mini waffle maker according to the manufacturer's instructions and preheat it for about 5 minutes, or until the indicator light shows it's ready.

Once your waffle maker is preheated, spoon half of the brownie batter into the center of the hot plates. Sprinkle half of the 2 tablespoons of sugar-free semi-sweet chocolate chips on top, and close the lid. Cook for 2-3 minutes, or until no steam escapes and the sides begin to crisp.

Carefully remove the first waffle using a fork, being cautious of the hot surfaces. Repeat the cooking process with the remaining batter, adding the rest of the chocolate chips to the second waffle.

Serve your delicious brownie waffles warm off the iron, either plain or topped with sugar-free maple syrup, keto ice cream, or whipped cream.