Cut the chicken into pieces, wash and drain well.
Heat oil in a pan and brown the chicken pieces on high heat in batches; keep aside.
If necessary, add more oil and add the sliced onions to the same pan. Saute till golden brown.
Add garlic, chilli flakes and stir through for another 30 seconds. Then add the tomatoes and cook till soft and pulpy.
Add the stock, saffron, cinnamon and lemon peel; then add the chicken pieces and bring to boil. Season with salt if necessary.
Turn down the heat and simmer for 45 minutes or till the chicken pieces are soft and tender.
Meanwhile, toast the pine nuts and keep aside. (Take care to keep on low heat as these burn easily).
Once the chicken is done, add the washed spinach leaves and stir through for another one minute and take off heat.
Check seasoning and garnish with toasted pine nuts.
Tuck in!