Skillet Cookie

Name: Skillet Cookie
Prep time: 10 min
Cook time: 20 min
Total time: 30 min
Yield: 8
Ingredients: Ingredients; 1/2 cup (1 stick) unsalted butter; 1/2 cup brown sugar, packed; 1/4 cup granulated sugar; 1 large egg; 1 teaspoon vanilla extract; 1 cup all-purpose flour; 1/2 teaspoon baking soda; 1/2 teaspoon salt; 3/4 cup chocolate chips; 1/4 cup chopped walnuts (optional); Vanilla ice cream for serving; Sea salt flakes for garnish (optional)