Heat oil in a Dutch oven on medium. Add onion, garlic and chili powder and cook until softened, stirring often, about 7 minutes. Stir in salsa and chicken broth, then whisk in Homemade Nutella. Season chicken with 1/2 teaspoon salt and add to the pot. Simmer until chicken is tender and cooked through, about 30 minutes. Serve with yellow rice, sprinkled with sesame seeds and scallions if desired.