Add the pecan halves to a medium saucepan over medium-low heat. Toast, stirring often until fragrant, about 3-4 minutes. Add the half and half, heavy cream, pinch of salt and brown sugar. Simmer, stirring often, until the sugar is dissolved, about 4-5 minutes. Remove from the heat, cover, and let the mixture steep for 15 minutes.
Whisk the egg yolks in a medium bowl until light in color and smooth. Add the cream mixture to the egg mixture in small amounts until you have included about half the mixture. Whisk in the remainder of the cream mixture and return to the saucepan over low heat. Cook, stirring often until mixture reaches 175 degrees. Do not allow the mixture to boil. At this stage the mixture will be slightly thickened and will coat the back of a spoon. Remove from heat. Pour the custard through a fine-mesh sieve over a bowl. Discard pecans. Let cool on counter for 30 minutes. Stir in the vanilla, cover and place in refrigerator overnight.
Pour into an ice cream maker and process according to the manufacturer's directions. (about 20-30 minutes depending on your machine) Add the glazed pecans during the last 2-3 minutes of mixing. Place mixture in a shallow airtight container and freeze for 3-4 hours for a firmer consistency.