Fajitas Stir-Fry
["1 lb. lean boneless beef steak or chicken breasts", "2 Tbsp. salad oil", "2 cloves garlic, minced or pressed", "1 large onion, thinly sliced and separated into rings", "2 or 3 fresh jalapeno chilies, seeded and minced", "1 large red bell pepper, seeded and cut into strips", "2 tsp. ground cumin", "3 Tbsp. lime juice", "1 tsp. cornstarch", "2 medium size Roma type tomatoes, diced", "salt and pepper", "lime wedges", "sour cream (optional)", "1 large ripe avocado, pitted, peeled and diced", "8 warm flour tortillas", "homemade or purchased salsa (optional)"]
["Cut beef or chicken with the grain into 1-inch wide strips, then cut each strip across the grain into 1/8-inch thick slices. Set aside."]
["beef", "salad oil", "garlic", "onion", "jalapeno chilies", "red bell pepper", "ground cumin", "lime juice", "cornstarch", "tomatoes", "salt", "lime wedges", "sour cream", "avocado", "flour tortillas", "salsa"]