Ingredients
1 1/4 cups whole milk
1/2 cup packed basil sprigs, plus small leaves for serving
5 teaspoons gelatin (from three 1/4-ounce envelopes)
3 cups fresh grapefruit juice, strained, plus supremes for serving
2 cups plain yogurt (not Greek)
1/2 cup honey
Flaky sea salt, such as Jacobsen or Maldon, for serving
Preparation
Combine 3/4 cup milk and basil sprigs in a small saucepan; bring to a simmer over medium-high heat. Cover, remove from heat, and let steep 20 minutes. Meanwhile, in a bowl, sprinkle 2 teaspoons gelatin over remaining 1/2 cup milk. In a heatproof bowl, sprinkle remaining 3 teaspoons gelatin over 1/2 cup grapefruit juice.
Let both mixtures stand until gelatin softens, about 5 minutes. Strain milk-basil mixture, discarding sprigs. Pour over milk-gelatin mixture and stir until gelatin has dissolved, then whisk in yogurt until smooth. Wipe pan clean.
Combine 3/4 cup grapefruit juice and honey in saucepan. Heat over medium-high, stirring, until honey dissolves and mixture is hot but not boiling. Pour over grapefruit-gelatin mixture, stirring until gelatin has dissolved. Stir in remaining 1 3/4 cups grapefruit juice.
Divide grapefruit mixture evenly among eight 6-to-8-ounce ramekins, gratin dishes, or shallow bowls. Refrigerate until mixture begins to thicken and mound slightly but isn’t set, 45 to 55 minutes. (Do not refrigerate yogurt mixture.)
Carefully divide yogurt mixture evenly among ramekins, pouring it in from edge (not center) of each dish to create a random swirl effect. Refrigerate until both mixtures are cold and set, about 4 hours or, covered, up to 3 days. Before serving, top with grapefruit supremes, basil leaves, and a sprinkle of salt.
