2. Heat one tablespoon oil in a large saucepan over medium high heat. saute shallot and onion until soft and translucent. stir in butter, lemon juice, ginger-garlic paste, 1 tspn garam masala, cayenne pepper, cumin and bay leaf. cook, stirring for one minute and add crushed tomato and cook for 2 mins, stirring frequently. stir in half and half and yogurt and reduce heat to low and simmer for about 15 minutes, stirring from time to time. season with salt and pepper to taste, remove from heat.
3. heat one tablespoon oil in a large heavy skillet over medium heat. add one tablespoon of tomato paste, stir a bit, and then add in chicken. cook chickenuntil lightly browned, about 10 minutes. reduce heat and if you like you can sprinkle a lil bit of garam masala and cayenne pepper on it as well (although it is already marinated in tandoori powder, so it's not necessary). stir in a few spoonfuls of sauce and simmier until liquid is reduced and chicken is fully cooked.
4. stir the cooked chicken into the sauce and cook for 5-10 minutes, until thickened. garnish with coriander and green chilis. serve with rice or naan.