Unroll skirt steak and cut crosswise into pieces that will fit your grill and place in baking dish. Combine lime juice, jalapeno, garlic, cumin and olive oil. Pour 2/3 of the marinade over your meat. Marinate for at least 2 hours if possible. Save the remainder for the vegetables.
When ready to grill, toss your vegetables with the remaining marinade. Heat grill or broiler. If you are not using a grill, heat a pan over medium-high heat with olive oil. Sauté or grill veggies until tender.
Remove the steak from the marinade, scraping off any garlic or chili that sticks to it. Place on pan under broiler or on hot grill. The steak, depending on its size, will only take a few minutes on each side, so watch closely. When done, remove from heat and slice.
Place meat and sautéed vegetables on plates with warm tortillas and fixings.
Nutrition Information: Calories 401; Saturated Fat 5g; Cholesterol 77mg; Sodium 338mg; Total Carbohydrates 31g; Dietary Fiber 4g, and Protein 29g.