For a spicier kick, add an extra teaspoon of hot sauce or a pinch of red pepper flakes to the sauce. If you don't have nectarines, peaches or plums work beautifully as a substitute. To thicken the sauce further, you can whisk in a cornstarch slurry (1 tablespoon cornstarch mixed with 2 tablespoons cold water) during the last few minutes of cooking. Consider adding a splash of rice vinegar or lemon juice for extra tanginess.