Sweet and salty coalesce in this easy ice cream recipe from "Martha" in-house chef Thomas Joseph.
Make the ice cream base: In a large saucepan, mix together cream, milk, vanilla bean, and seeds over medium-high heat until small bubbles form. In a large bowl, whisk together sugar and egg yolks. Slowly whisk one-third of the hot cream mixture into egg mixture. Transfer egg mixture to saucepan with remaining cream mixture and continue to cook, whisking, until thickened, 4 to 5 minutes. Strain through a fine mesh sieve set over a bowl; set aside while you make the caramel.
Make the salted caramel: In a small saucepan, combine sugar and 3 tablespoons water; mixture should look like wet sand. Place saucepan over medium-high heat and cook until sugar is dark amber in color. Remove from heat and immediately add cream and salt; let cool slightly.
Add salted caramel to ice cream base; whisk to combine. Cover mixture with plastic wrap and refrigerate until cold, 2 to 3 hours and up to overnight. Freeze ice cream in an ice cream or gelato maker according to manufacturer's instructions.
Make the caramel crunch: Line a rimmed baking sheet with a nonstick baking mat; set aside. In a small saucepan, combine sugar and 3 tablespoons water; mixture should look like wet sand. Place saucepan over medium-high heat and cook until sugar is dark amber in color. Immediately pour caramel onto prepared baking sheet; let cool completely.
Crack cooled caramel into large pieces and place in a resealable plastic bag. Crush into tiny pieces using a rolling pin; you should have a scant cup of caramel crunch. When ice cream is almost finished freezing, add 1/2 cup caramel crunch. Transfer to a 1 1/2-quart loaf pan or container and freeze until set, at least 2 to 3 hours and up to overnight. Serve sprinkled with sea salt and remaining caramel crunch.