Place lemon juice and sugar in a small saucepan and bring to a simmer over medium heat, stir until the sugar is dissolved. Remove from the heat and refrigerate the thin syrup until chilled.
Add the milk, cream, and honey in a medium heavy bottom saucepan, bring to a soft boil. Remove pan from the heat, stir in the basil leaves, and 2 tablespoons of lemon zest. Cover the pan with plastic wrap to trap the steam. Let steep for 30 minutes to hour.
Set a mesh wire sieve over a large bowl, near the stove.
Place the egg yolks in a medium bowl, whisk well and set them next to the stove.
100 grams egg yolks
Scoop the basil out of the cream with a slotted spoon and return the sauce pan to medium heat, stirring occasionally.
When the temperature of the cream reaches 113℉ (45℃) on instant thermometer, stir in the sugar. Followed by slowly pouring in the egg yolks while continuously whisking.
133 grams granulated sugar
TIP: The temperature is low enough that the eggs can be tempered directly into the sugared cream. OR you can ladle out 1 cup (250 grams) of the hot cream and slowly drizzle it into the bowl of yolks while whisking, then pour that mixture back into the saucepan while whisking to temper the eggs.
Now that the egg yolks have been added to the cream, continue to gently stir while cooking the custard base until it reaches 182℉ (83℃) on the thermometer.
The ice cream base is cooked when it reaches the desired temperature, when it coats the back of a spoon and you can easily draw a line through the custard with your finger tip.
Immediately remove the pan from heat and strain the custard through a wire mesh sieve into a large bowl to catch any leftover zest or possible cooked egg.
Stir in the salt, vanilla and extra tablespoon of lemon zest. Let the base cool at room temperature, with an occasional stir. (stir in the lemon syrup or wait until churning)
1.5 teaspoons vanilla extract, pinch of flaky sea salt
Place a piece of plastic wrap directly onto the custard and refrigerate until chilled through, minimum 4 hours. For best results leave it in the fridge overnight.
Churn and Freeze
TIP: Blend cold base a few seconds with an immersion blender to smooth.
Pour the cold base into to your ice cream maker and churn according to the manufacturer's instructions. While churning pour in the lemon syrup if you haven’t already. My machine usually takes around 25-28 minutes.
Spoon into a freezer safe container with a lid and freeze for several hours before scooping.
Since this ice cream has a 2:1 ratio of cream to milk, it will be very creamy and easy to scoop.