In a medium saucepan, combine the heavy cream and whole milk over medium heat, stirring occasionally. Heat until small bubbles begin to form around the edges, approximately 5–6 minutes, but do not let it boil.

While the cream mixture heats, whisk together the egg yolks, granulated sugar, and brown sugar in a separate bowl until the mixture is pale and creamy. Once your cream is heated, slowly drizzle it into the egg mixture while continuously whisking.

Return the combined mixture back to the saucepan and reduce the heat to low. Stir continuously with a wooden spoon until the custard thickens and reaches about 170°F, which should take around 5–7 minutes.

Once thickened, strain the custard through a fine mesh sieve into a bowl to remove any lumps and ensure that your ice cream is silky smooth. Stir in the vanilla extract and a pinch of salt for flavor enhancement. Allow the mixture to cool at room temperature for about 30 minutes before transferring it to the fridge to chill for at least 4 hours.

While the custard chills, melt the unsalted butter in a skillet over medium heat. Add the chopped pecans, toasting them for about 3–4 minutes until they're golden and fragrant.

After the custard has chilled adequately, pour it into your ice cream maker and churn according to the manufacturer’s instructions. In the last few minutes of churning, fold in the cooled toasted pecans.

Once churning is complete, transfer the ice cream to an airtight container. Cover it tightly and place it in the freezer for at least 4 hours to allow it to firm up nicely.