Khatte chole, a popular Indian street food, was our starting point for this quick-and-easy vegetarian curry. Amchoor, or dried green mango powder, usually supplies the dish's characteristic tartness, but instead we steep chopped onion and jalapeño in lemon juice to make a quick pickle that adds crunch as well as acidity. For less heat, remove the seeds from the jalapeño before chopping. A box grater makes quick work of reducing the onions and tomatoes to a pulp—no food processor or blender needed. Serve the chickpeas with naan or basmati rice.