Add spices and gently fry for about 1 minute until the seeds start to pop, stir to prevent any burning of these spices.
Add the onion and ginger and garlic paste and cook until the onion is softened for about 5 to 7 minutes.
Add chopped tomatoes and cook until softened for about 10 minutes and keep stirring regularly.
Carefully remove these cooked ingredients to a blender or use a stick blender to blitz to a paste and then return to the pan.
Add the lentils and chicken stock, bring the curry to the boil and once boiling turn down to simmer for about 15 to 20 minutes until the lentils have softened. Add extra boiled water from a kettle if necessary then add the salt to taste.
Add the chopped chicken and cook the chicken within the lentil mixture for about 15 minutes until the chicken is cooked through.