Chicken Fajitas with Bell Peppers

Name: Chicken Fajitas with Bell Peppers
Ingredients: 1/4 cup vegetable oil, divided; 3 medium cloves garlic, minced; 1/4 teaspoon kosher or sea salt, plus more for seasoning; 1/2 teaspoon chile powder; 1/4 teaspoon ground cumin; 1/2 teaspoon paprika; 1/4 teaspoon sugar; 2 teaspoons fresh lime juice; 1 pound boneless, skinless chicken breasts, sliced in strips; 1 medium onion, sliced; 1 red bell pepper, seeded and sliced; 1 green bell pepper, seeded and sliced; 1 orange bell pepper, seeded and sliced; Fresh cracked black pepper; Flour or corn tortillas, for serving; Shredded cheese and sour cream, for serving (optional); Chopped avocado, chopped cilantro and salsa or chopped tomatoes, for serving (optional)