Preheat the oven to 350 degrees and grease a 10-inch cast iron skillet.
In a medium bowl, stir together the flour, baking soda, cinnamon, and salt. Set aside.
In a large bowl, combine the eggs, coconut oil, maple syrup, pumpkin puree, and vanilla extract.
Add the dry ingredients to the wet ingredients and mix well. Then stir in the chocolate chips.
Transfer the batter to the prepared skillet. Bake for 35 to 40 minutes, or until the top is set and the edges are starting to crack a bit. My family prefers it on the slightly gooey, undercooked side, but you can leave it in for up to 40 minutes (or longer) if you want it cooked all the way through.
Cool on a wire rack.