Season the chicken. Heat 2 tbsp of the oil in a flameproof dish, then brown the chicken on all sides. Remove the chicken to a plate.
Blend the chopped onion, tomatoes, ginger and garlic into a rough paste. Fry the sliced onion in the remaining oil in the dish until softened, then add the spices and fry for 1 minute more, until fragrant. Add the paste and fry for another few mins to soften.
Return the chicken to the dish with the squash, stock, sugar and vinegar. Bring to a simmer, then cook for 30 mins until the chicken is cooked through. Lift the chicken out and stir in the cherries, then continue simmering the sauce to thicken while you shred the chicken into bite-sized chunks. Stir the chicken back into the sauce and season.
Mix the red onion, lemon zest, mint and feta. Scatter over the dish, then serve with some couscous and yogurt.