Baked Sweet Potato Chaat

Name: Baked Sweet Potato Chaat
Ingredients: 4 medium sweet potatoes (about 2½ lb.); 2 Tbsp. plus ½ cup extra-virgin olive oil, divided; Kosher salt; 2 15.5-oz. cans chickpeas, rinsed, patted dry; 1 Tbsp. ground cumin; 1 Tbsp. chaat masala, plus more for fried onions; 1 bunch cilantro; 4 scallions, coarsely chopped; 1 jalapeño, halved, ribs and seeds removed, coarsely chopped; ¼ cup fresh lime juice; ⅓ cup store-bought fried onions; ⅔ cup plain whole-milk yogurt; ½ small red onion, finely chopped; Pomegranate seeds and mild chile flakes (for serving)