Heat up grill. In a small bowl, mix oil and garlic together. Brush the chicken breasts with 1 teaspoon of the oil mixture and sprinkle with seasoned salt. Place on grill over medium-high heat and cover grill. Cook for 12-18 minutes,turning once, until juices are gone from chicken. Reduce heat to medium-low.
Place tortillas on ungreased cookie sheets. Brush the remaining oil mixture on tortillas. Sprinkle each tortilla with 1/4 cup of the mozzarella cheese. Cut the chicken into strips and arrange on top of the cheese. Add the tomato slices, sprinkle the remaining cheese and add the basil.
With a spatula, carefully slide the pizzas onto the grill over medium-low heat. Cover the grill and let cook 3-5 minutes. (rotate the pizzas around to avoid hot spots). Once cheese is melted, remove the pizzas off the grill and serve. Enjoy!