Before beginning, make sure your ice cream maker is fully frozen and ready to do.
Add the sugar and egg yolks to a large, heat-safe mixing bowl. Use an electric hand mixer to whip until fluffy and lightened in colour, 2-3 minutes. Set aside.
Pour the milk and cream into a saucepan. Heat over medium, stirring frequently, until almost boiling (once it starts to bubble, turn off the heat).
Slowly pour ¼ cup of the hot milk into the sugar mixture, stirring as you pour. This tempers the eggs, preventing curdling.
Add the remaining milk in a low stream, stirring constantly, until fully incorporated. Whisk in the lemon zest.
Pour the milk mixture back into the saucepan. Cook over low heat, stirring constantly, until thickened. This should take about 10 minutes, and the custard is ready when it coats the back of a wooden spoon.
Pour the lemon juice into the custard and whisk to incorporate.
To quickly cool the custard, pour it into a heat-safe bowl and place it into an ice bath, stirring to speed cooling even more. It should come to room temperature in a few minutes. Alternatively, cover and set aside to cool.
Once the custard has cooled, cover and place it into the refrigerator to chill for about two hours. Once chilled, it should be thickened and cold to the touch.
Pour the chilled custard into your ice cream maker and churn according to manufacturer’s instructions.
Once the ice cream has churned, scoop it into a container with a lid. Stir in the meringue pieces, then swirl in the lemon curd. You can add the curd in two layers (add half the ice cream, swirl, then add the remaining ice cream and swirl again) to ensure that it’s evenly incorporated.
Freeze the ice cream in an airtight container for up to one month. Thaw in the refrigerator for 10 minutes before scooping and serving.