This one appears in Mud Puddle's Cocktail Handbook by Jeff Masson and Greg Boehm and was adopted from a recipe appearing in the 1953 edition of the United Kingdom Bartenders' Guild Guide To Drinks.
1 1/2 oz (45 ml) Jamaican dark rum
1 ounce (30 ml) yellow Chartreuse
1/2 ounce (15 ml) white creme de cacao
1/2 ounce (15 ml) lime juice
1 dash grenadine
Shake with ice and strain into a cocktail glass.
Wow this one's good! Big rum, the chocolate is subtle and the yellow Chartreuse brings it all together. With only 1/2 ounce of lime juice this is a more booze forward sour.
I used Smith & Cross for the Jamaican rum and subbed in Mozart Dry for the white creme de cacao.
The dash of grenadine providing a little color and just a touch of sweet to back those boozy flavors off a bit.
The results are a deep dark & earthy "daiquiri-style" drink. A challenging drink, but very much "yum" in my book.