Make the hot cocoa. Prepare 1/2 cup of hot cocoa slightly richer than usual. If using a mix, use a little less water or add a splash of milk.
You want a thick, chocolatey base.
Chill your glass. Place a martini glass in the freezer for 5 minutes. A cold glass helps the drink stay silky and balanced.
Optional: Rim the glass. Lightly brush the rim with simple syrup or honey, then dip into crushed cookies, cocoa powder, or grated chocolate. Set aside.
Build the cocktail. In a shaker, add ice, then pour in 1.5 oz vodka, 1 oz chocolate liqueur, 0.5 oz coffee liqueur (optional), 0.25 tsp vanilla extract (or swap to vanilla vodka), and the warm 1/2 cup hot cocoa.
Shake briefly, but firmly. Shake for about 10–12 seconds.
The goal is to chill and aerate without watering it down too much.
Taste and adjust. If you want it richer, add a splash (0.5 oz) of half-and-half or heavy cream and shake again. For sweeter, add a small drizzle of chocolate syrup.
Strain and serve. Double strain into your chilled martini glass for a smooth, frothy finish.
Garnish. Top with whipped cream, dust with cocoa, add chocolate shavings, or float a toasted marshmallow on a cocktail pick.