Preheat the oven to 350 degrees F and line a baking sheet with parchment paper (or spray with cooking oil).

Whisk the egg in a mixing bowl, then stir in the peanut butter until very thick, creamy, and well-combined. Add the remaining ingredients to the bowl and mix until combined.

Note: you can also mix the cookie dough in a stand mixer or use an electric hand mixer).

Roll dough into balls and place on a baking sheet. Use a fork to press crisscross indentations into the balls of dough.

Bake for 8 to 10 minutes on the center rack of the preheated oven - 8 for chewier cookies, 10 for crispier cookies.

Allow cookies to cool for 10 minutes before serving.