To Make the Custard Base
In a medium saucepan, bring sugar, honey, milk, and salt to a low boil over medium heat.
In a separate bowl, whisk the egg yolks. Temper the egg yolks by slowly pouring the hot milk mixture over them while continuously whisking.
Pour the custard base back into the saucepan and cook on medium-low heat. Constantly whisk the custard base until it is smooth and thick. Tip: coat a spoon in the custard base, then draw a line across the back of the spoon with your fingertip. If the line remains clear, the custard base is ready.
In another separate bowl, add the heavy cream and vanilla extract. Pour the custard base through a fine mesh strainer over the bowl of heavy cream and vanilla extract. This ensures a smooth custard base in case you have any bits of cooked eggs.
Stir the custard base until thoroughly mixed. Press (cover) plastic wrap on the surface of the custard base to prevent forming a skin layer. Place in the refrigerator and chill. It should be at least 40°F before churning.
To Make the Lemon Curd
Whisk together the eggs and egg yolks in a medium-sized bowl.
In a medium saucepan, bring sugar and lemon juice to a boil over medium heat. Remove the saucepan from the heat and temper the eggs by slowly adding the lemon syrup into the bowl while whisking to prevent the eggs from curdling.
Pour the mixture back into the saucepan and cook on medium heat. Constantly whisk the lemon curd until it thickens, about 3 - 5 minutes, or until it coats the back of a spoon (like the custard base). While whisking, add a few pieces of the cubed butter at a time into the lemon curd. Once the butter is fully melted and incorporated, remove the saucepan from the heat.
Pour the lemon curd through a fine mesh strainer by using a spatula to push it through. Press (cover) plastic wrap on the surface of the lemon curd to prevent forming a skin layer. Chill in the refrigerator.
To Make the Lemon Pie Ice Cream
Pour the chilled custard base into the ice cream machine and churn according to the manufacturer's directions. Typically, it's the lowest speed for 15 - 20 minutes. Stop churning and add the lemon curd once the ice cream is the consistency of soft-serve ice cream. Churn for 3 to 5 more minutes until the ice cream is smooth and thick and sticks to the machine's arm.
Transfer the ice cream to a freezer-safe container. Quickly fold in crushed graham crackers. Enjoy the Lemon Pie Ice Cream now, or cover and freeze it for at least 2 hours. When you are ready, scoop and enjoy!