Foundation Prep: Begin by preparing your produce. Dice the yellow onion, mince the garlic cloves, and carefully peel and cube the butternut squash. Set each component aside.
Sauté the Aromatics: Place the Dutch oven over medium heat. Add a swirl of neutral oil. Once warm, add the chopped onion and cook, stirring occasionally, until softened and translucent, about 6–7 minutes. Add the minced garlic and continue to cook for one minute more until fragrant.
Bloom the Spices: Stir the tomato paste, chili powder, cumin, smoked paprika, and chipotle powder into the onions and garlic. Cook for 60 seconds, stirring constantly, to toast the spices and deepen their flavor.
Brown the Turkey: Add the ground turkey to the Dutch oven. Use a wooden spoon to break it into smaller pieces. Cook until the meat is fully browned with no pink remaining, approximately 7–8 minutes.
Assemble the Chili: Carefully transfer the entire contents of the Dutch oven into the insert of your slow cooker. Add the cubed butternut squash, rinsed black beans, fire-roasted tomatoes, crushed tomatoes, chicken broth, and salt. Stir thoroughly to combine all ingredients.
Slow Simmer: Secure the lid on the slow cooker. Set the temperature to LOW for 7–9 hours or to HIGH for 4–5 hours. The chili is ready when the squash is fork-tender and the flavors have melded together beautifully.
Serve and Garnish: Give the finished chili a final stir. Ladle into warm bowls. Top with a sprinkle of cotija cheese, a scattering of fresh green onions, and serve with a lime wedge on the side for squeezing.