In a saucepan, combine whole milk, sugar, and 1 cup of heavy cream. Warm this mixture over medium heat, stirring until it begins to bubble, then remove it from heat.

Add fresh mint leaves to the warm milk mixture and let it steep for 1-2 hours.

In a bowl, whisk egg yolks until smooth, then temper by slowly adding a bit of the warm mint mixture while whisking, then pour this back into the saucepan.

Heat gently, stirring constantly until it thickens slightly, then strain through a fine mesh sieve to remove mint leaves.

Stir in the remaining heavy cream and chill in the refrigerator for at least 2 hours or overnight.

Pour the chilled mixture into your ice cream maker and churn according to the manufacturer's instructions until thick and creamy.

In a food processor, puree watermelon, sugar, and lemon juice until smooth. Transfer to a shallow, freezer-proof dish.

Freeze for about 3-4 hours, scraping with a fork every 30 minutes until it’s fluffy and fully frozen.

To serve, layer scoops of the fresh mint ice cream with the salted watermelon granita in elegant bowls.