Spread the pecan halves on a small baking sheet in a single layer and toast in a 350º F oven until fragrant, 12-14 minutes. Let the nuts cool, then use your fingers to break each half into 4-8 pieces.
Reduce the oven temperature to 275º F.
In a medium-large saucepan, melt the butter with the brown sugar and salt.
Remove from heat let cool 30 seconds then gently whisk in the eggs one at a time, then the maple syrup, vanilla and 2 tablespoons of the bourbon.
Return the pot to a low heat and cook, stirring constantly with a heat-proof rubber spatula, until the mixture is warm to the touch (130ºF on an instant-read thermometer).
Remove from the heat and whisk in the remaining 2 tablespoons of bourbon and the pecan pieces.
Pour the mixture into the prepared pie shell.
Bake the pie at 275º until the custard is mostly set, 25-40 minutes.
Recipe by Chef Tom Cooks ! at https://cheftomcooks.com/2017/01/07/maple-bourbon-pecan-pie/