Whisk egg yolks in a medium sized heat proof bowl.
Heat 3/4 cup of the milk and the maple syrup in a medium saucepan set to medium heat, stirring occasionally, until it begins to steam.
Once the milk mixture just begins to steam, slowly pour it into the whisked egg yolks, 1/4 cup at a time, while whisking constantly.
Add the egg yolk mixture bag to the pot and continue cooking over medium heat, whisking constantly, until it thickens.
Once the custard has thickened, transfer to the refrigerator to cool.
In a large pot, add water and salt and bring to a boil.
Add fresh basil leaves and boil for 1 minute, then strain out the water.
Add the rest of the milk, the heavy cream, blanched basil leaves, vanilla extract, and salt to a high speed blender. Blend until smooth.
Pour the blended mixture of milk, basil and cream through a fine-mesh sieve set over a medium bowl to remove the fibrous plant material. Use the back of a wooden spoon to or rubber spatula to help move the ice cream base through the sieve.
Pour mixture of cooled custard into the bowl with rest of the ingredients and combine well with a whisk.
Transfer ice cream base to the bowl of the ice cream maker.
Allow ice cream maker to complete the churning process until a thick, creamy ice cream is formed.
Enjoy!