1 pound small Yukon Gold potatoes, scrubbed
1 small onion, chopped
2 serrano chile, seeds removed if desired, chopped
1 2-inch piece ginger, peeled, chopped
1 cup chopped fresh cilantro, plus more for serving
¼ cup vegetable oil
1 can chickpeas, rinsed, patted dry
Freshly ground black pepper
2 teaspoons chaat masala
2 tablespoons prepared tamarind chutney, divided
pinch of sugar
1 cup raita yogurt
¼ cup sev or similar/fried noodles