line a baking sheet with parchment or foil, set aside
place a heavy bottom saucepan on a burner
add brown sugar, water, vanilla, cinnamon, and salt if using
turn on the burner to medium
cook and stir until the mixtures comes to a boil, boil without scorching for 1-2 minutes
add the pecans and stir to coat, cook for another minute or two, again do not scorch this mixture
spread on the prepared pan to cool
if you want the pecans separated now is the time to do it while they're warm
if you want to sprinkle on Maldon Sea salt do it when the pecans are spread on the pan and still warm