Stir grapefruit juice, Seedlip, lime syrup and juice to mix in an 8 to 10 oz glass. Carefully fill glass 1/2 to 2/3 with selzter, gently stir. Add ice. Garnish with a grapefruit twist or lime wedge if desired.
Lime Syrup (adapted from Stella Parks' fresh lemon syrup recipe found at Serious Eats)
Cut the lime rinds into large chunks. Combine with sugar in a glass jar or non-reactive bowl. Cover tightly. Stir periodically (every 30 to 60 minutes) until the sugar has dissolved (several hours).
Strain syrup through a fine mesh strainer, into another glass jar or glass measure. Transfer the rinds in batches to ricer and squeeze so the juice passes through the strainer. Store in the refrigerator; it should keep for 2 to 3 months.
I am an amateur baker and cake decorator. I enjoy cooking, as well as eating and feeding others. I live in the beautiful Pacific Northwest with my husband and our menagerie. I enjoy outdoor activities including hiking, mushroom hunting, tide pooling, beach combing, and snowboarding.