Heat the oven to 350°F.
Melt the butter in a 10-inch oven-safe skillet over low heat. Take the skillet off the heat.
Stir in the brown sugar and granulated sugar until smooth. Let the mixture cool for 5 minutes.
Stir in the egg and vanilla until glossy.
Sprinkle the flour, baking soda and salt over the top and stir just until no dry flour remains. Stir in the chocolate chips and smooth the dough into an even layer.
Bake for 18–22 minutes, until the edges are golden and the center is just set.
Cool for 10 minutes. Serve warm, straight from the skillet, with ice cream.