Brown Butter Toffee Chocolate Chip Cookies

Instructions

Line a baking sheet with parchment. Melt the toffee butter, brown sugar and salt in a saucepan over medium heat, adding a little water if the fat starts to separate. Cook to 150°C (302°F), the point where a drop in water forms brittle threads.

Pour the toffee onto the lined sheet and freeze it for about 30 minutes, until hard. Meanwhile, line a second baking sheet with parchment.

Melt the butter for the dough in a saucepan and cook it until it turns dark brown, then take it off the heat. Drop in one ice cube and let it melt, then repeat with the other three.

Whisk the white and brown sugars, espresso powder, salt and baking soda together in a large bowl. Pour in the brown butter and beat until combined, then beat in the eggs and vanilla. Fold in the flour until no dry streaks remain.

Break the frozen toffee into chunks, seal them in a zippable bag and crush them into small bits with a rolling pin. Fold the toffee and chopped chocolate into the dough.

Scoop the dough onto the prepared sheet and chill it for 48 hours so the flavors develop.

When you are ready to bake, heat the oven to 163°C (325°F) and line two baking sheets with parchment. Arrange the cookies on them with at least 2 inches (5 cm) between each one.

Bake for 18 to 20 minutes, until golden brown. Sprinkle the cookies with a little flaky sea salt as they come out of the oven, and leave them to cool.