Preheat the oven to 350F and grease a 6.5-inch cast iron skillet with coconut oil or butter.
In a mixing bowl, whisk together the coconut sugar and melted coconut oil until fully combined. Whisk in the egg and vanilla until the mixture is uniform.
Add the almond flour, baking soda, and salt to the bowl and mix until combined. The dough should be relatively thick and sticky.
Fold in the chocolate chips, reserving some for topping. Transfer the dough to the skillet and ensure the dough is evenly spread. Top with reserved chocolate chips and flaky salt (if desired).
Bake until the top of the cookie is golden brown and a toothpick comes out clean, 17 to 20 minutes. For an extra gooey center, bake for closer to 17 minutes.
Cool the skillet for at least 10 minutes before cutting and serving. Optionally top with whipped cream, ice cream or a caramel drizzle.
