1. Prepare the Grape Puree

1. In a medium saucepan, combine the grapes, sugar, and lemon juice.
2. Cook over medium heat, stirring occasionally, until the grapes break down and release their juices, about 10 minutes.
3. Use a potato masher or the back of a spoon to crush the grapes for maximum flavor.

2. Strain the Mixture

1. Remove the saucepan from heat and strain the grape mixture through a fine mesh sieve into a bowl, discarding the solids.
2. Let the puree cool to room temperature.

3. Make the Ice Cream Base

1. In a large bowl, whisk together the heavy cream, whole milk, sweetened condensed milk, vanilla extract, and the cooled grape puree.

4. Churn the Ice Cream

1. Pour the mixture into your ice cream maker and churn according to the manufacturer’s instructions, typically 20–25 minutes.
2. If you don’t have an ice cream maker, pour the mixture into a shallow dish and freeze, stirring every 30 minutes to break up ice crystals until creamy (about 4–6 hours).

5. Freeze Until Firm

1. Transfer the churned ice cream to an airtight container and freeze for at least 2 hours or until firm.