Preheat your oven to 350°F, and line a light-colored baking sheet with parchment paper. Make sure your trays are ready before mixing, this dough should go straight into the oven once it’s made.
In a large bowl, whisk together the melted (cooled) butter, brown sugar, granulated sugar, and corn syrup until glossy and smooth, about 1 minute. Add egg and vanilla:
1/2 cup unsalted butter, 115 g light brown sugar, 1/4 cup granulated sugar, 2 tsp corn syrup, 1 large egg, 1 tsp vanilla butter emulsion
Whisk in the egg and vanilla until the mixture thickens slightly and looks shiny.
Fold the dry ingredients into the wet mixture just until combined, do not overmix. Add chocolate chips and fold evenly through the dough.
145 g all-purpose flour, 2 tsp cornstarch, ⅛ tsp baking soda, ⅛ tsp baking powder, ¾ tsp salt, 1/2 cup semi-sweet or dark chocolate chips
Scoop about 3 tablespoons (≈60 g) of dough per cookie (you’ll get about 12 cookies).
Place them on the prepared sheet, spacing about 4 inches apart. Bake for 9 minutes, or until the edges are light golden and the centers still look soft and glossy.
(Optional: bang the tray once around the 6-minute mark for rippled edges.)
Let cookies cool on the tray for 6–8 minutes, then transfer to a wire rack.
They’ll settle into thin, chewy cookies with crisp edges and buttery, bendy centers.