Preheat oven to 350 degrees Fahrenheit.
Fit the chilled pie crust into a 9-inch pie dish and crimp the edges.
Toast the pecan halves in a dry pan over medium heat for 5 minutes, then set aside.
In a large mixing bowl, whisk together the eggs, brown sugar, salt, and vanilla until smooth.
Slowly pour the maple syrup into the egg mixture while stirring continuously.
Add the melted butter and whisk until the mixture is uniform.
Scatter the toasted pecans evenly across the bottom of the unbaked pie crust.
Pour the maple custard mixture over the pecans.
Bake for 50 minutes until the center is set but still slightly wobbly.
Remove from the oven and allow to cool completely on a wire rack before slicing.