Jupiter's Acorn

From the wonderful Craigie on Main in Cambridge, with a nod to the original poster of the recipe.

1 oz Barbancourt 15 Year Rum
1 oz Nux Alpina Walnut Liqueur
1/2 oz Punt e Mes (or Sweet Vermouth)
1/2 oz Benedictine
1 Egg
1 dash Angostura Bitters
1 dash Mole Bitters

Combine in a glass and shake for 5-10 seconds. Add ice and shake for 20-30 seconds. Strain into a cocktail glass and top with grated nutmeg.