Ah Scrappy's, my favorite bitters producer. Their grapefruit bitters smell just like fresh grapefruit. But be careful! If you're used to a few strong dashes with classics like Angostura I find that one dash will do with Scrappy's. These are powerful in both flavor and bitterness, so it is easy to go overboard. My favorite use for the Grapefruit is in a classic 2:1 Martini with a juniper and citrus forward gin. Stir 2 oz Citadelle Gin, 1 oz Dolin Dry with one dash of Scrappy's Grapefruit. Dolin Dry is still a touch sweet and the dash of bitters does a good job of offsetting the sugar. Finish with a lemon twist. Cheers!