Preheat the oven to 350 degrees F. Lightly grease an 8-inch cast iron skillet and set aside.
In a small bowl, combine the almond flour, baking soda, and salt. In a large bowl, whisk together the egg, maple syrup, coconut oil, and vanilla extract. Add the dry ingredients to the wet ingredients and whisk or stir until well combined.
Fold in the grated zucchini and blueberries, and stir. Transfer the batter to the skillet and use a rubber spatula to spread it out. Sprinkle the chocolate chips on top of the cookie.
Bake for 25-30 minutes, or until the edges are brown and slightly crispy.
Enjoy warm, right out of the skillet!
This can be sliced into pieces if you want to serve more people. They will be more fragile than a regular cookie but shouldn't fall apart. Store in an airtight container in the fridge for a few days.