To prepare the steak: Combine the tequila, lime juice, salt, black pepper, sugar, and habaneros in a large resealable plastic bag and shake until well mixed. Add the steaks and shake again. Make sure that both steaks are well coated with marinade. Refrigerate for 8 hours.
Meanwhile, to make the peppers and onions: Preheat the grill to low to medium. Lay a double layer of 3-foot-long heavy duty foil on your counter. Place the bell peppers and onions in the center and sprinkle with the oil, salt, and black pepper. Fold the ends of the foil to the center to create a foil pouch and seal all loose ends. Poke 2 or 3 fork holes in the top and place on the grill until softened, about 15 minutes.
When ready to cook the steak, preheat the grill to high for 10 minutes. Reduce the heat to medium and grill the steaks 4 to 5 minutes on each side for medium-rare. Cut each steak into 4 equal portions.
To serve, place a heaping scoop of the grilled vegetables in the center of a dinner plate and top with the steak.