Instructions

1. Preheat oven to 325º. Put 1⁄2 cup of the sugar and 3 tbsp. water into a small heavy-bottomed saucepan, cover, and boil over medium-high heat until sugar dissolves, 2–3 minutes. Uncover and cook until sugar turns a deep amber and reaches 310º on a candy thermometer, about 5 minutes. Working quickly, carefully pour equal amounts of the hot caramel into four 5-oz. custard molds, then swirl caramel to coat insides of molds halfway up sides and set aside.
2. Heat milk in a medium saucepan over medium heat until hot. Whisk together eggs, the remaining 1⁄2 cup sugar, port or anisette, and lemon zest in a medium bowl. Gradually whisk in hot milk. Strain custard through a sieve into a bowl, then divide between prepared molds.
3. Arrange custards in a medium baking dish. Add enough boiling water to the dish to reach halfway up sides of molds. Transfer to oven and bake until custards are just set and centers are slightly soft when molds are jiggled, 40-45 minutes. Remove molds from water bath, allow to cool briefly, then refrigerate until cold, about 3 hours.
4. To serve, run a small knife around inside edge of each mold and invert custard onto a dessert plate, pouring caramel on top.