In a large jar, combine the vodka and lemon zest. Seal and let it infuse for at least 7 days in a cool, dark place.

After 7 days, strain the mixture through a fine mesh strainer to remove the zest.

In a saucepan, combine the sugar and water. Heat over medium heat until the sugar dissolves completely. Let it cool.

Combine the lemon-infused vodka with the sugar syrup in a large bowl.

In a blender, combine the heavy cream and sweetened condensed milk. Blend until smooth.

Gently fold the cream mixture into the limoncello base until well combined.

Pour the crema di limoncello into clean bottles and seal tightly.

Refrigerate for at least 24 hours before serving to allow flavors to meld.