In a saucepan, simmer the cream and half-and-half on medium heat until warm, do not let it come to a boil. Turn off the heat, add the lavender to the pot, cover, and let steep for half an hour.
After the flowers have steeped, strain the liquid and discard the flowers. Stir into the cream the honey and heat on medium low until the honey has dissolved. Again, do not let liquid come to a boil.
Beat the egg yolks with the vanilla, lemon juice, lemon zest, and salt. Stir into the eggs 1/2 cup of the warm liquid and then stir the eggs into the pot.
Heat this on medium low for 5 minutes or until it gets slightly thick. You’ll know it’s ready when it coats the back of your spoon. Cool in the refrigerator for 4 hours.
Freeze and churn according to your ice-cream maker’s instructions. Will keep covered in the freezer for 2 weeks.
Notes
If you taste the custard before churning and find it’s not sweet enough for you, I suggest sweetening it more with sugar rather then honey as honey’s strong flavor can overpower the lavender.