Source: Rachel Ray

1 1/2 cups plain yogurt
Juice of 2 limes (1/3 cup)
2 tablespoons extra-virgin olive oil plus 1/4 cup for brushing vegetables
1 tablespoon hot pepper sauce
2 tablespoons chopped fresh thyme leaves, a few sprigs
1 (1 1/2 pound) sirloin steak or flank steak
2 red or green bell peppers, halved and seeds removed
1 large sweet onion, such as Vidalia, Maui or Texas Sweet
Salt and pepper, to taste
1 jalape? pepper, seeded and coarsely chopped
1/2 cup cilantro leaves, loosely packed
1 teaspoon salt
8 to 12 large flour tortillas
2 yellow, orange or red vine-ripe tomatoes, chopped

Preheat a grill pan or electric grill to high heat, or prepare outdoor grill.

In a shallow dish, combine the juice of 1 1/2 limes (reserving 1/2 lime) with 2 tablespoons olive oil, hot pepper sauce and chopped thyme leaves. Coat beef in the lime-oil. Grill beef 6 or 7 minutes on each side.

Baste pepper halves with a little oil, and set on grill alongside beef. Cut onion into 4 or 5 thick slices, cutting across the onion. Remove outer ring of the sliced onion, discarding the skin. Baste onion with oil and place on grill. Season beef and vegetables with salt and pepper. Peppers and onions will grill in about 10 minutes. They should be charred at edges, but still have a bite to them.

In a food processor, combine yogurt, the juice of reserved 1/2 lime, the jalape? pepper, cilantro leaves and salt. Process the ingredients into a smooth, green sauce.

Once you remove beef and vegetables from the grill, char and warm tortillas. Slice cooked beef on an angle and transfer to a serving plate. Slice peppers into strips and cut onion rings in half. Transfer cut veggies to platter alongside beef.

To assemble, pile beef, pepper strips and onions into tortillas and top with chopped tomatoes and lots of yogurt green sauce.

Makes 4 to 6 servings.