In a large saucepan, add chopped onions, cashew nuts, cassia bark, cardamom, bay leaf, green chillies and roughly 1 litre of water, bring to boil, cover with a lid and simmer for 30 minutes.
Transfer to a shallow tray to cool. Remove whole spices and green chillies and blitz the onion and cashew into a smooth paste, set aside.
In a large sauce pan, heat 1 tbsp of ghee then add yogurt and khoya and cook over medium heat, stirring constantly for 5 minutes, then add the puréed onion-cashew sauce, salt and simmer for 20 minutes and set aside. Cut each chicken breast into 4 or 5 pieces, add ginger-garlic paste, salt, cardamom powder and yogurt; mix well and set aside.
Heat 1 tbsp of ghee and add the marinated chicken and sauté over medium heat for 5 minutes, then add the cooked onion-cashew sauce and simmer for 15 minutes or until the chicken is cooked through. Check seasoning, add saffron, edamame peas and single cream. Mix well and serve garnished with dehydrated rose petals and toasted almond flakes.