Petals of red onion, nutty acorn squash, and pickled peperoncini tossed in a creamy Italian dressing make a hearty but not heavy side. Inspired by chef Scott Tacinelli’s crispy sweet potatoes at Don Angie in New York, we’re adding sumac to the dressing, giving it an herbal, lemony kick.
Squash mixture may stand at room temperature up to 3 hours in advance. Serve at room temperature, or reheat in a 425°F oven until warmed through, about 5 minutes. Yogurt mixture may be prepared up to 2 days in advance and stored in an airtight container in refrigerator.