Heat oil in a large saucepan over medium heat. Saute onions until soft and translucent. Stir in lemon juice , butter, ginger-garlic paste, 2 teaspoons garam masala, and cumin. Cook, stirring for about two minutes. Add tomato sauce and blend in and cook for another two minutes. Stir in yogurt and half/half -coffee cream). Reduce heat and simmer for 5 min. Remove and set aside
Heat 1 Tbls oil and a teaspoon butter in large skillet over medium heat. Cut Chicken into cubes and cook about 10 minutes. Reduce heat and add 1 teaspoon garam masala and a dash of cayenne. Add your sauce to the chicken and cook on low till chicken is no longer pink inside.
Serve over Basmati Rice and garnish with fresh cilantro.