3 large egg yolks
¾ cup sugar
2 cups heavy (whipping) cream
½ cup whole milk
5 medium peaches (1¾-2 pounds)
1 teaspoon almond extract
Juice of half a lemon
Fresh raspberries or sliced peaches, for serving (optional)
In a medium bowl, whisk together egg yolks and ½ cup of the sugar. Set aside.
Fill a large bowl halfway with ice and cold water. Set out a smaller bowl (with a minimum capacity of 2 quarts) that will fit inside the larger bowl.
In the top of a double boiler set over simmering water, heat the cream and milk until bubbles just begin to form on the surface. Do not let the mixture boil.
Add about ½ cup of the hot cream to the egg yolk mixture and whisk briskly to combine. Stir yolk mixture into the remaining cream in the double boiler and whisk well. Cook over simmering water, stirring constantly with a stainless steel or wooden spoon, until the mixture thickens slightly and coats the back of the spoon, about 5 minutes. Remove from the heat and pour into the smaller bowl that you have set out. Place this bowl into the prepared ice-water bath. Stir gently to cool the mixture.
When the ice cream base is cooled to room temperature, cover and refrigerate until thoroughly chilled, at least 2 hours or overnight (recommended).
Bring a pot of water to a boil. Meanwhile, use a sharp paring knife to cut an X in the bottom of the skin of each peach. Working in batches, plunge the peaches into the boiling water for 1 to 2 minutes, remove with a slotted spoon and, when cool enough to handle, slip off the peels. Cut the peaches in half, remove and discard the pits, and cut the flesh into ¼-inch pieces. You should have about 2 cups of fruit.
Sprinkle the peaches with the remaining ¼ cup of sugar, the almond extract and lemon juice. Let the peaches sit at least 30 minutes at room temperature for the flavors to blend.
Purée half of the peaches in the bowl of a food processor or in a blender. Stir the peach purée into the chilled ice cream base. Then stir in the remaining cup of peach chunks.
Freeze the mixture in an ice cream maker following the manufacturer's instructions. You can serve it immediately, or pack it into an airtight plastic container and freeze until firm, 3 to 4 hours. It will keep for several weeks in the freezer.
Serve with sliced peaches or raspberries, if desired.
Makes six cups; serves 12.