Heat olive oil in a wok or skillet over medium-high heat. Add garlic, ginger and onions – stir-fry 1 minute. Add quail breast pieces and stir-fry for 1 minute more. Add 5-Spice, soy sauce, hoisin and chili sauce (if desired). Allow mixture to cool. Lay foil squares on counter or surface. Place 1 quail breast half on the center of each foil square. Drizzle sauce equally over quail. Add additional hoisin, if desired. Fold foil over into a triangle and fold edges over to seal triangles. Heat oil to 360 degrees. Place foil triangles, a few at a time, in hot oil until they float to the top, about 2 minutes. Drain on paper towels and serve immediately.