In a small dish, combine the cumin, coriander, salt, and cayenne pepper. Sprinkle both sides of the chicken with the spice mixture. Heat the oil in a large skillet. Saute the chicken over medium-high heat for 4 - 5 minutes until golden brown and cooked through. Remove chicken from the skillet and keep warm. Add the garlic and gingerroot to the skillet and sauté, stirring for about 45 seconds. Add the vinegar and soy sauce and simmer, stirring, about 30 seconds. Spoon the sauce over the chicken and garnish with the green onions. Serve with cooked Chinese noodles or Chow Mein Noodles and a salad of shredded red cabbage and lettuce.