To a bowl mix diced chicken with yogurt, garam masala, cumin, ground coriander, turmeric, chilli powder, salt, garlic, ginger and lemon juice, allowing to marinade for at least an hour.
Then, begin by peeling, chopping and par boiling potatoes for 10-12 minutes.
Fry the chicken on a medium high heat with oil for 3-4 minutes, then set aside.
To the same pan, add butter and fry diced onion for a couple of minutes until golden.
Then, add garlic, ginger and tomato puree mixing through.
Add, garam masala, cumin, paprika and salt, stirring through.
Then, add tomatoes, tinned or fresh and stir through.
Bring to a gentle simmer then add cashews with a splash of water, stirring through.
Then, using a stick or jug blender, blitz the sauce until smooth.
Return the sauce to the pan, bring to a simmer then add cream and sugar, stirring through.
Return the chicken to the pan and stir through.
Add fresh coriander allowing a couple of minutes to simmer, before transferring to an ovenproof dish.
When the potatoes are ready, add melted butter, garam masala, paprika, garlic granules and salt, mixing until fully coated.
Then, evenly place the potatoes on top and place in a preheated oven at 180c (fan) for 40-45 minutes or until the potatoes are golden.
