From Curry Cuisine, p. 132.
Ground lamb and kidney curry. Keema, or ground meat, is the staple food in every household, every roadside restaurant, and every cafeteria in Pakistan, and keema is probably the first curry to be mastered and consumed over and over again by every Pakistani student in the US or UK. The meat was traditionally beef; then mutton or lamb became popular. Nowadays among the urban population, ground chicken is picking up. Vegetables, such as potatoes, peas and onions, lentils, and beans are often added for flavour and to extend the dish. But kidneys lift ordinary keema to a higher status, making this curry worthy to be served to a special guest. Instead of including kidneys, you can, of course, add potatoes or peas. Serve this with plain yogurt and pratha.
Pour 1 cup water into a small saucepan. Layer the sliced kidneys in the pan, cut side down. Add 1/2 tsp of the garlic paste and 1/2 tsp turmeric. Bring to a boil, then drain the kidneys. This helps to remove their strong smell.
Heat the oil in a saucepan, add the onions, and cook until golden brown. Add the remaining garlic paste, the ginger paste, and tomatoes and stir well, then add the chili powder, remaining turmeric, the cumin seeds, ground coriander, and salt. Cook, stirring, until the oil separates out.
Add the ground lamb and stir to mix with the massalla. Add the kidneys and mix them in. Put the lid on the saucepan and cook for 30-35 minutes over low heat.
Remove the lid and cook for a further 8-10 minutes or until excess liquid has evaporated and the oil separates out.
Stir in the chopped cilantro. Garnish with green chilies and ginger and serve.
The curry can be made in advance (it's good for freezing) and then reheated in the pan or in a microwave.
17-06-07: 207 g onion, 273 g beef kidney, 326 g tomato, 526 g ground camel. Total finished weight: 962 g, split into 8 portions.