The edges are perfectly crispy and crunchy, rich with the brown sugar flavor. And the inside is a gooey and delicious mess that my husband described as cookie stew. Weird, but I love him anyways.
By the way, I bought the skillets recommended in the original post. For us, they are totally worth it for these cookies alone. Make a double batch, and freeze the extra dough in cookie-sized portions.
3/4 cup flour
3/4 tsp. baking soda
1/2 tsp. fine sea or kosher salt
1/4 tsp. ground cinnamon
6 Tbsp. butter, room temperature
2/3 cup packed light brown sugar
1 large egg
1 tsp. vanilla
2/3 cup rolled oats
1/2 cup dark chocolate chunks or chips
Flaked sea salt
Preheat oven to 350°F. Lightly butter or grease 8 mini (3.5-inch diameter) cast iron skillets. Arrange on a baking sheet.
In a bowl, whisk together flour, baking soda, salt and cinnamon until incorporated. Set aside.
In a mixing bowl, beat butter and sugar until light and fluffy, 2 to 3 minutes. Mix in egg and vanilla, scraping down the side of the bowl as needed. Add dry ingredients and oats, and mix until just incorporated. Stir in chocolate chunks.
Spoon dough into 2-inch diameter balls, approximately 2 tablespoons per ball. Drop balls into prepared skillets. Top with a few more chocolate chunks and a sprinkle of flake salt (if desired). (Dough balls can also be frozen on a lined cookie sheet until frozen solid, and then transferred to a zip top bag for later use.)
Bake for 14 to 16 minutes or until edges are golden and center is just set but not overcooked. If you like your cookies gooey, err on the side of underdone. If you like your cookies crispy, cook for a minute or two longer. Add one minute of cook time if cooking dough from frozen, and do not thaw first.
Makes 8 skillet cookies.