1) Heat the oil in a large frying pan over medium heat until shimmering. Add the onions and cook, stirring occasionally, until softened, about 5 minutes.
2) Add the garlic, chili powder, cumin, oregano, paprika and black pepper, stir to coat the onion, and cook until fragrant, about 1 minute. Add the ground turkey and salt and cook, breaking the meat into small pieces with a wooden spoon, until the beef is no longer pink, about 7 minutes.
3) Transfer the mixture to the slow cooker, add the diced tomatoes, tomato paste, broth, beans, and corn. Stir to combine. Cover and cook until the chili thickens and the flavors unite, about 8 hours on low or 6 hours on high.
4) Taste and season with salt as needed, and serve with the cheese, scallions, sour cream or any of your favourite accoutrements!