In a medium saucepan over medium heat, combine the heavy cream and whole milk. Warm the mixture until tiny bubbles form around the edges, about 5-6 minutes.

In a separate bowl, whisk the egg yolks with the granulated and brown sugars until pale and creamy.

Slowly add half of the hot milk mixture to the egg yolks while whisking continuously to temper.

Return the entire mixture back to the saucepan and cook over low heat until thickened, about 7-10 minutes.

Strain the custard through a fine mesh strainer into a bowl. Stir in the vanilla and salt, and chill for at least 4 hours.

Melt the unsalted butter in a skillet, add chopped pecans, and toast until golden brown, about 3-4 minutes. Transfer to cool.

Churn the chilled custard in an ice cream maker according to the manufacturer’s instructions, adding the pecans in the last few minutes.

Transfer to a freezer-safe container and freeze for at least 4 hours until firm.