Spray a wide-based saucepan or sauté pan with oil and place over a medium heat. Cook the onions for five minutes, stirring regularly, until softened and very lightly browned.
Cut the chicken thighs in half and add to the pan. Cook for two minutes, turning occasionally. Stir in the garlic, ginger, garam masala and chilli powder and cook for a few seconds, stirring constantly.
Tip the tomatoes into the pan and add the chicken stock, lentils and bay leaves. Bring to the boil, then cover loosely with a lid and simmer gently for 35 minutes, or until the chicken is tender and the lentils have completely broken down, stirring occasionally. Remove the lid for the last 10 minutes of cooking time, stirring regularly so the lentils don’t stick.
About 25 minutes before the curry is ready, cook the rice in plenty of boiling water until tender, then drain well.
Season the curry to taste. Serve with the rice, topped with yoghurt and sprinkled with coriander.