This recipe is from my very well thumbed and stained copy of ” Madhur Jaffrey’s Indian Cookery”. This was the first Indian cookery book i bought, but one i still return to regularly. You can make this in advance and reheat if you like.
Trim the beans and cut them crosswise into 1/2-inch lengths. Put the ginger and garlic into the container of an electric blender or food processor. Add 1/2 cup of water and blend until fairly smooth.
Put the oil in a wide, heavy pot over medium heat. When hot, put in the cumin seeds. Five seconds later, put in the crushed chile or crushed red pepper flakes. As soon as it darkens, pour in the ginger-garlic paste. Stir and cook for about a minute.
Put in the coriander. Stir a few times. Add the chopped tomatoes. Stir and cook for about 2 minutes, mashing up the tomato pieces with the back of a slotted spoon as you do.
Put in the beans, salt (maybe not all of it to start), and the remaining water. Bring to a simmer. Cover, turn heat to low, and cook for 8 to 10 minutes or until the beans are tender. Remove the cover and add the juice of half a lemon, the ground roasted cumin seeds (if using), and a generous amount of freshly ground black pepper. Increase heat and boil away all the liquid.
Taste and adjust with more lemon, salt, or pepper as necessary.