How to make it
Make the pickled red onions, if desired: Place the onion, bay leaves and cinnamon stick in a small tempered glass or ceramic dish. In a small saucepan, bring the vinegar, water, salt, and sugar to a simmer, stirring occasionally. Pour over onions, let sit in refrigerator for one hour or overnight. May be prepared up to one week in advance.
Preheat the oven to 350 degrees and wash the squash and cut in half. Cut a small slice off each of the bottoms so that the squash will sit flat. Scoop out seeds and pulp and discard. Toss the squash with olive oil and season with salt. Bake in oven on a small sheet tray until they are tender enough to pierce with a fork, about 25 minutes.
Toss the chickpeas with the harissa and lime juice, season with salt.
Layer into the squash halves with feta, olives, mint, scallions, and pickled onions if using.