Brush the grill racks with oil and heat the grill to very hot. Meanwhile, prepare the sauce and the guacamole. To prepare the sauce, heat the olive oil in a medium saucepan over high heat until very hot. Add the garlic and onion and saute lightly for 2 to 3 minutes. Add the chiles, tomatoes, and tomato puree and cook over high heat for about 5 minutes. Add the olives and oregano and cook for about 5 minutes. With a handheld blender, coarsely puree the sauce in the pan. Alternatively, transfer the sauce to the bowl of a food processor and blend, then return to the pan. Season to taste with salt and pepper and keep warm. To prepare the guacamole, cut the avocados in half, remove the pits, and scoop the flesh out of the skins into a medium bowl. Add the garlic, tomato, onion, and lime juice and mash with a potato masher. Stir in the cumin and cayenne sauce. Season to taste with salt and pepper. Cover the bowl with plastic wrap and place in the refrigerator until ready to use. To prepare the steak, rub the meat with olive oil and season it on both sides with salt and pepper. Place the meat on the very hot grill and cook for 2 to 3 minutes per side for rare to medium-rare doneness. Remove meat from the grill, place on a cutting board, and slice thinly against the grain at a 45-degree angle. Place the slices on a serving platter or individual plates and spoon warm sauce generously over the slices. Top with a dollop of guacamole and serve hot. Per serving: 113 Calories (kcal); 5g Total Fat; (39% calories from fat); 5g Protein; 13g Carbohydrate; 9mg Cholesterol; 188mg Sodium Food Exchanges: 0 Grain(Starch); 1/2 Lean Meat; 2 Vegetable; 0 Fruit; 1/2 Fat; 0 Other Carbohydrates Converted by MM_Buster v2.0n.