Fill a small squeeze bottle with your favorite chocolate sauce. Create a spiral pattern of chocolate in the martini glasses, turning each glass gently as you squeeze out the sauce.
Squeeze a generous amount of chocolate sauce onto 4 cherries, and place in the bottom of each glass.
Fill a metal cocktail shaker with cracked ice; place the top on the shaker, and shake for about 10 to 15 seconds. Add the vodkas, chocolate liqueurs, Kahlua and half-and-half, and shake until frothy, about another 15 seconds.
Strain the liquid into the prepared glasses, and serve immediately.