01 -
Get your oven going at 350°F, then cover a large baking tray with parchment paper.
02 -
Use a stand mixer to beat the butter with both sugars until creamy. Add yolk, vanilla, and food color, then mix until smooth.
03 -
Toss in the flour, cocoa, baking powder, and salt, then stir until the dough forms and no flour streaks are left.
04 -
Roll the dough into 18 balls, coat them with red sanding sugar, and place them on the prepared tray.
05 -
Cook for about 10 minutes, then stick a chocolate kiss in the middle of every warm cookie. Leave to cool on the tray for 10 minutes before moving to a rack.