01 -
Beat cocoa powder, sugar, and oil until shiny black dough forms.
02 -
Mix in eggs one at a time for 30 seconds each. Add vanilla and beat well.
03 -
Whisk flour, baking powder, salt, and espresso powder. Mix into chocolate mixture until just combined.
04 -
Cover dough with plastic wrap and chill 4 hours or overnight.
05 -
Roll dough into 1-inch balls, coat in powdered sugar. Place on lined baking sheets.
06 -
Bake at 350°F for 10-13 minutes. Cool briefly on sheets then transfer to rack.