Pick up some squash blossoms at the farmers' market and make these itty bitty frittatas!
In medium bowl, toss zucchini, onion, and oil; season. Grill over high heat, turning often, until charred in spots, 5 to 8 minutes. Chop zucchini and onion. Coat 12 nonstick muffin cups with cooking spray. Divide zucchini, onion, and feta among cups. In bowl, whisk eggs and half-and-half; season. Divide among cups. Bake at 300° until just set, about 20 minutes. If using squash blossoms, spray lightly with cooking spray and place on top of frittatas during last minute of cooking.