Make small incisions in the chicken drumsticks and keep them in a bowl. To marinate the chicken drumsticks, add ginger garlic paste, red chilli paste, chaat masala, salt and lemon juice to the bowl and mix well. Set aside. For the tandoori masala, in a different bowl, take yogurt and whisk it well. Add ginger garlic paste red chilli paste, chaat masala, black salt and lemon juice. Mix them all. Add salt and garam masala and mix again. Pour the entire masala in the chicken bowl and mix well. Set the chicken bowl aside for three hours so that the masala is absorbed well. Add oil and arrange the chicken legs on a baking tray with the entire marinade. Bake in a pre heated oven at 170 C for 15 to 20 minutes. Arrange the lettuce leaves, onions, tomatoes and the green bell pepper (all sliced) on a plate, forming a circle. Keep the baked chicken legs at the centre. Garnish with green chutney and mint leaves to serve.