Lemon Ginger Blackberry Swirl Ice Cream

In a heavy saucepan, bring cream and milk to a simmer. Stir in lemon peels and ginger, cover, and remove from heat.

Let steep for 1 hour.

Purée blackberries in a blender or food processor just until they break apart into a liquid and no large chunks remain (see note above). Slowly pour purée through a strainer and gently stir with a fork or whisk. Measure out 1 1/2 cups strained juice and discard blackberry pulp.

In a heavy saucepan, bring strained blackberry juice to a simmer on medium heat and reduce to 1/2 cup, stirring frequently. Stir in 1/2 cup sugar and 1/4 teaspoon salt until dissolved.

Transfer to a small container and chill in refrigerator.

In a clean, heavy saucepan, whisk together 3/4 cups sugar with egg yolks until pale in color and thickened. When dairy finishes steeping, pour through a strainer into pot and whisk to combine with yolk-sugar mixture. Put saucepan on medium heat and cook, stirring frequently, until a custard forms on the back of a spoon, but a finger swiped across the back leaves a clean line.

Add 1/2 teaspoon salt.

Pour through a stainer into an airtight container and refrigerate overnight.

The next day, churn in ice cream maker according to manufacturer's instructions. While ice cream is churning, remove blackberry syrup from freezer and stir to loosen.

Transfer 1/3 of finished ice cream into an airtight container, then quickly spread on half of syrup. Repeat, and top off with last 1/3 of ice cream. Chill in freezer until firm, at least three hours, preferably longer.