"The San Martin" has an unusual taste--not unpleasant--just unusual, and its taste kind of caught me offguard. I love virtually all hard liquors, but my mainstay is gin, and I've had many drinks with a gin and sweet vermouth combination. But this one... I made the drink using Bombay Saphire gin, Vya sweet vermouth, and (of course) 1 tsp of yellow Chartruse. I think it's the yellow Chartruse that's got me bamboozled.
Perhaps a different sweet vermouth will do better (e.g., the ol' standbys, Dolin or Antica Formula). The Chartruse is nicely placed in this drink; barely perceptible, but there. Maybe 1/4 or 1/2 more gin may make for a more satisfying taste and drink. Puzzle this one out for me, please. I did rate the drink at 3.5, however.