In a large skillet (or your stovetop proof slow cooker insert), heat the oil over medium heat.
Add chicken, cornstarch, salt and pepper to a large bowl. Toss to coat the chicken completely. Cooking in batches, add the chicken to the skillet and brown on all sides. Transfer to a plate and repeat with the remaining chicken.
Transfer the chicken to the slow cooker.
In a small bowl, whisk together the Harry & David Pepper and Onion Relish, turmeric, garam masala, cumin, cayenne pepper, tomato sauce and ginger.
Pour the mixture over the chicken. Add the squash, chicken stock, cinnamon stick and peppers to the slow cooker. Stir to combine.
Cover and cook on low for 6 hours or high for 4 hours.
Ten minutes prior to serving, stir in the half and half and spinach.
Serve with rice and chopped cilantro, if desired.