Rinse chicken, pat dry with paper towels. Slash meaty parts of chicken two or three times.
Place chicken in a shallow non-metal dish and set aside.
Put tomatoes, tomato paste, chili sauce, sugar, garam masala, soy sauce, gingerroot, garlic, limejuice, and lemon juice in a blender and process until pureed.
Pour over chicken, cover, and refrigerate 2-3 hours to marinade.
Preheat oven to 375° Fahrenheit. Put chicken and the sauce in a roasting pan and cook, uncovered for 45-50 minutes, or until tender, basting with sauce two or three times during cooking.
Serve hot, garnished with twists of lime and lemon.