2tablespoonsunsalted butter, melted and slightly cooled
2tablespoonslight brown sugar, packed
1tablespoongranulated sugar
1largeegg yolk (save the white for something else)
1/2teaspoonvanilla extract
1/4cupplus 1 tablespoon all-purpose flour (36 g)
1/8teaspoonbaking soda
Pinch of fine salt
3tablespoonssemisweet chocolate chips or chopped chocolate
Optional: a pinch of flaky sea salt for topping
Instructions
Prep the pan: Heat the oven to 350°F (175°C). Lightly butter a 6-inch oven-safe skillet or two 6-ounce ramekins.
Mix the wet ingredients: In a small bowl, whisk the melted butter, brown sugar, and granulated sugar until glossy.
Whisk in the egg yolk and vanilla until smooth.
Add the dry ingredients: Sprinkle in the flour, baking soda, and salt. Stir until just combined. Do not overmix.
Fold in chocolate: Stir in the chocolate chips. The dough will be thick and soft.
Fill and smooth: Press the dough into the skillet (or divide between ramekins).
Smooth the top and add a few extra chips.
Bake: Bake 12–15 minutes until the edges are set and golden but the center is still a little soft. For ramekins, start checking at 11 minutes.
Finish and serve: Let it rest 5 minutes. Sprinkle with flaky salt if you like.
Enjoy warm as-is or with a scoop of vanilla ice cream.