In a medium-size saucepan, bring the stock and meat glaze (if using) to a boil over medium-high to high heat. Reduce the heat to medium.
Whisk the dissolved arrowroot into the gently boiling stock. Whisk vigorously until the sauce thickens and lightly coats a spoon, 15 to 20 seconds, and remove from the heat. Season with the salt and pepper. (This thickened sto