This is my version of the rummer served at the King’s Arms Tavern in Colonial Williamsburg, Virginia. It is advertised as an authentic colonial-period cocktail. Be aware: Sip it slowly. It goes down deceptively but can kick like a mule —it’s pure liquor — so don’t have anywhere to go when you mix this up.
NOTE: If you don’t have the Blackstrap, use 3 ounces of regular dark rum. But the Blackstrap is the “secret ingredient” that I guarantee your guests will not be able to figure out!