Peach Ice Cream

INSTRUCTIONS

Prepare the custard base:

1. Put the egg yolks in a medium stainless-steel mixing bowl and float that bowl in a larger bowl half full of hot tap water. Whisk the yolks until they are lukewarm, between 90 to 100℉ (it will take less than a minute), then lift the bowl out of the water and set aside.
2. Combine 1 cup + 2 tablespoons sugar, milk, and cream in a 2-quart saucepan and bring it to a boil over medium-high heat. The instant the cream comes to a rolling boil and begins rising in the pan, lift it off the heat. With the whisk in one hand and the saucepan in the other, pour the boiling cream into the egg yolks as you whisk constantly but gently. (Don't whisk rapidly or you will cool the custard before the yolks have a chance to set.) Continue to stir the custard with a whisk for 1 minute. At this point it should be fully cooked (an instant-read thermometer set in the custard should register 170 to 180℉. It will coat a teaspoon, but it will become much thicker as it cools. (If the custard did not get hot enough to thicken, you can place the bowl on top of a saucepan of boiling water and stir it with a rubber spatula until it reaches 170℉.) Whisk the sauce rapidly for 30 seconds to cool it, then pour it through a fine sieve. Add the vanilla extract. Set it aside to cool.

Prepare the peaches:

1. Combine the peach slices, 1/2 cup sugar, and the lemon juice in a bowl, then transfer to a 2-quart heavy saucepan and boil, covered, over high heat, stirring occasionally, for 10 minutes. The simmer, uncovered, stirring occasionally, 30 minutes more.
2. Purée the hot mixture in a blender until smooth, about 1 minute. Force it through a sieve into the custard mixture, pressing on the solids with the back of a spoon and discarding them. Cool to room temperature, stirring occasionally, about 45 minutes.
3. Stir together the custard base and the peach mixture and refrigerate until chilled. Freeze in an ice cream maker according to the manufacturer's directions.