01 -
Heat butter in a steel pan on medium until the solids turn golden brown (around 10 minutes). Pour it all, including the browned bits, into a bowl.
02 -
Stir the espresso powder into the butter and let it cool completely, roughly 20-30 minutes.
03 -
Stir both sugars into the cooled butter for about a minute until nice and blended.
04 -
Mix in the egg, yolk, and vanilla until no lumps remain.
05 -
Fold in the flour, salt, baking soda, and chocolate until just mixed—don't overmix!
06 -
Scoop dough onto a tray lined with parchment, then freeze for at least 4 hours or even overnight.
07 -
Heat your oven to 350°F (180°C). Place the chilled dough on a tray, spaced 2 inches apart, and bake for 10-12 minutes until the edges are golden but the middle stays soft.
08 -
Place cookies on a cooling rack while still on the tray and let them cool down.