Heat vegetable oil in a large Dutch oven over medium heat. Season chicken with salt and pepper and place skin side down in to the pan. Cook until golden brown without turning, about 8?10 minutes. Transfer chicken to a plate.
To the same pot, add onion, garlic, and ginger to pot and cook, stirring occasionally, until onion is very soft and golden brown, about 8?10 minutes. Add tomato paste, garam masala, cumin, turmeric, coriander, cayenne and cook, stirring often, until tomato paste is beginning to darken, about 4 minutes.
Add chicken pieces, chicken broth, tomato purée, and cream to pot. Season with salt and pepper and bring to a boil. Reduce heat and simmer, partially covered, until chicken is almost falling off the bone and liquid is slightly thickened, about 1 1/2 hours. If using bone-in chicken, remove chicken to a plate and carefully remove chicken from the bone and discard skin and bones. Cut or pull chicken into bite-sized pieces. Return chicken pieces to the pot.
Add potatoes