You can use any flavor ice cream that suits your fancy, but I prefer the traditional combination of chocolate-cookies-and-vanilla-ice-cream. Using store-bought ice cream is fine, but for a homemade treat make your own vanilla ice cream. Other homemade flavor suggestions would be Chocolate Mint Chip Gelato, Chocolate Mint Marshmallow Ice Cream, or Caramel Swirl Almond Gelato. You can even use dairy-free ice cream for gluten-free dairy-free ice cream sandwiches.