Let's answer the question you're asking yourself. What distinguishes gelato from ice cream is the following: more egg yolks, less cream/more milk, and definitely less air churned into it than ice cream.
The key to expressing that dense and creamy note is dry ice. Dry ice is not only cold enough to solidify the base. What's more, (unlike regular ice) dry ice sublimes into a gas, leaving nothing to dilute gelato's intensity of flavors.
A word of caution: avoid touching the dry ice with your bare hands.
Mint Gelato Base
1/2 c Heavy Cream
1 1/2 c Whole Milk
1/2 Vanilla Bean, split
1/2 tsp Vanilla Extract
4 oz Granulated Sugar
4 oz Egg Yolks (about 8 large yolks)
6 sprigs Fresh Mint
1. In a medium saucepan combine the cream, milk, and vanilla bean. Bring to a boil over medium heat then turn off the burner.
2. Right as the milk comes to a boil whisk together the sugar and the egg yolks in a large mixing bowl. While still whisking, slowly pour the hot milk mixture into the eggs.
3. Return the mixture to the pot and add the mint. Put the pot back on the burner and turn the heat to medium-low. Stir constantly with a rubber spatula making sure to scrape the bottom of the pan. Continue to cook until the base starts to thicken and can coat the back of a spoon.
4. Immediately transfer the mixture to another mixing bowl in an icebath so as to cool it quickly.
5. Once the mixture has cooled completely strain the mixture and refrigerate until ready to use.
Mint Dry Ice Gelato
1 1/2 # Gelato Base (see above)
4 1/2 # Dry Ice
1. Wrap the dry ice in a towel and use a mallet or rolling pin to break it into small pieces.
2. Use a blender or food processor to turn small pieces of dry ice into a powder.
3. Place your gelato base in a standard mixer fitted with a paddle attachment, and churn at medium speed.
4. While churning, add dry ice to the bowl, a spoonful at a time, until gelato is thick enough to scoop.
5. Check the bottom of the mixer bowl for any settled dry ice, and use the mixer to stir it into the ice cream.
6. Let it sit for 10 to 20 minutes in the freezer to ensure that any remaining pieces of dry ice have had time to fully sublime.