Peel and chop ripe mangoes
Blend the mango pieces into a smooth puree
Whisk together heavy cream, milk, and sugar until the sugar dissolves
Add the mango puree and mix well
Stir in a little lemon juice if desired
Pour the mixture into a freezer-safe container
Freeze for 1 to 2 hours
Stir the mixture to break up ice crystals
Repeat stirring every 30 to 45 minutes until creamy
Freeze until firm
Scoop and serve