Preheat oven to 375° Fahrenheit. Liberally season each chicken breast with salt and pepper on both sides.

Heat avocado oil in cast iron skillet over medium heat. When hot, add chicken to skillet. Sear 3 to 4 minutes, then flip and sear on other side 3 minutes. Add a little more oil if chicken starts smoking

Remove pan from heat and transfer seared chicken to plate. Add garlic to skillet and cook until fragrant, approximately 1 to 2 minutes.

Stir in broth and coconut milk, then slowly add nutritional yeast, sun-dried tomatoes, oregano, salt, and red pepper flakes.

Return skillet to heat. Bring mixture to simmer, then return chicken breasts to skillet. Quickly flip chicken a time or two to coat in sauce, then transfer entire skillet to oven. Bake 15 to 20 minutes, or until chicken reaches internal temperature of 165° Fahrenheit.

Remove chicken from skillet and plate with desired sides. Spoon additional sauce from skillet over chicken, garnish with chiffonaded basil, and serve immediately.