Heat a grill pan over medium-high heat. Brush first 5 ingredients with 2 tablespoons olive oil. Cook corn cobs and onions in hot pan, turning occasionally, 5-6 minutes or until charred. Remove from pan. Cook peppers in pan for 5-6 minutes or until charred. Remove from pan. Cook tomatoes in pan for 2-3 minutes or until charred.
Rub steak with steak seasoning, and cook in pan over medium-high heat 5-6 minutes on each side or to desired degree of doneness. Remove from pan and let stand 5 minutes - then slice steak on the diagonal.
Cut corn kernels from the cob and place in a large bowl. Chop onion, bell pepper, poblano pepper and tomatoes. Combine with corn.
Stir together garlic, lime juice, salt and remaining 2 tbsp. oil -- add to chopped vegetables. Serve steak and salsa in heated or grilled tortillas with desired toppings -- sour cream, guacamole, or cheese.