Melt butter in sauce pan over medium heat.
Add pecans and cook until butter froths and pecans become fragrant. Stir constantly and be sure to watch that they don't burn. Should be about 5-7 minutes.
Remove pecans to another bowl and set aside. Remove pan with remaining butter from heat and set aside to cool.
Put cream and milk in a heavy bottom sauce pan over medium low heat and cook, stirring often, until it reaches a slow simmer.
While cream mixture is cooking, whisk eggs in a medium bowl for about 2 minutes. Add sugar slowly and whisk for another 1 minute.
Temper the egg mixture by adding a fourth of the simmering cream, whisking constantly. Add the remaining cream in a slow stream, whisking constantly. Return entire mixture to sauce pan and cook over medium low heat, stirring often, until it reaches a temperature of 170 degrees. Turn off burner and add the vanilla and reserved butter. Stir or whisk well.
Put mixture in a shallow bowl, cover, and let cool to room temperature. Once cool, put in fridge for an hour or two.
Pour mixture into the container of ice cream maker and freeze according to maker's directions.
After about 10 minutes in the ice cream maker, when ice cream is starting to firm up, add the pecans. Continue freezing to desired consistency.