1. In a large pan heat oil. Add chopped onions and sauté until golden, over medium-low heat. stir occasionally.
2. When onions are golden add grated garlic and ginger. Stir and cook for 2 minutes. Add chopped tomatoes and cook, stirring occasionally, until soft. Add curry powder and cook, stirring, for 2 minutes. Add chicken breast, season with salt and pepper, cook for 5 minutes, until golden. Cover the pan and cook for 2-3 minutes more. Add water, cover and cook 10 minutes.
3. Add coconut milk/cream, season with garam masala and salt, stir, and cook until lightly thickens.
4. Serve with naan bread or rice.