In a medium-sized bowl, whisk together the oil, balsamic and spices. Then, add chicken and toss to coat in the marinade. Cover the bowl with plastic wrap and refrigerate for at least 30 minutes, but preferably up to 4 hours.
1 lb chicken breast, 1.5 tbsp avocado oil, 1 tbsp balsamic vinegar, 1.5 tsp chili powder, 1 tsp cumin, 1 tsp kosher salt, ½ tsp coriander, ½ tsp black pepper, ¼ tsp red pepper flakes