Melt the butter, then let it cool for about 5–10 minutes until just warm (not hot). Whisk together melted butter, brown sugar, and white sugar. Add the egg and vanilla extract and mix until smooth.
Add flour, baking soda, cornstarch, and salt. Mix until a soft dough forms. Fold in the chocolate chips.
Chill the dough in the fridge for 30–60 minutes so it firms up and becomes easier to shape.
Preheat oven to 175°C (350°F). Press the chilled dough into a rectangle (about 1–1.5 cm thick). Slice into fry-shaped strips and transfer them onto a baking sheet lined with parchment paper.
Bake for 10-12 minutes, depending on thickness, until the edges turn lightly golden. If the dough spreads in the oven, remove the tray immediately and reshape the fries while hot using a spatula or knife.
Warm up some Nutella and serve as a dip. Enjoy fresh for the best texture.
