In a large bowl, combine curry powder, paprika, and salt for the marinade. Cut each chicken breast into 7-9 pieces. Stir the chicken pieces into the marinade until well coated. Cover and refrigerate for at least 1 hour, ideally up to 4 hours or overnight.
While the chicken is marinating, prepare the sauce. Heat 1 tbsp of oil in a large non-stick saucepan over medium heat. Add onions, garlic, and ginger. Cover and cook for 10 minutes until onions are lightly browned and soft, stirring occasionally.
Stir in curry powder and cook for 2 minutes, stirring frequently. Add tomato purée, caster sugar, and salt. Fry for another 30 seconds, stirring constantly.
Pour water into the pan and simmer gently for 5 minutes. Remove from heat and blend the sauce until smooth using a hand blender. Set aside.
Heat 1 tsp of oil in a large non-stick frying pan. Stir-fry the marinated chicken for about 3 minutes over medium-high heat until lightly colored.
Pour the prepared masala sauce into the pan with the chicken. Add cream and cook for 3-4 minutes longer, stirring until chicken is tender and cooked through. Add a little extra water if the sauce seems too thick.
Serve with rice and a large mixed salad, garnished with fresh coriander sprigs. Enjoy your guilt-free chicken tikka masala!