2 cups sugar
8 ounces cream cheese, at room temperature
2 large eggs
2 egg yolks
1 teaspoon vanilla extract
3 cups milk
2 cups whipping cream
4 teaspoons grated fresh lemon or orange zest (optional)
Beat the sugar and cream cheese together until smooth and creamy. Beat in the eggs and vanilla. Set aside. In a saucepan, bring milk to a simmer. Slowly beat the hot milk into the cream cheese mixture. Place back over medium heat and stir until it thickens slightly. Refrigerate until cold. Add in the whipping cream and the zest if desired. Freeze as directed.
For the raspberry swirl: Mix 3 cups frozen raspberries (thawed and drained) with powdered sugar (1 cup?) and mash together. Fold into ice cream while it's still soft before putting it in the freezer.