Roast the squash, if not using canned or pre-cooked squash.
Preheat the oven to 400° F, slice in half lengthwise, and scoop out the seeds. Lightly oil, salt, and pepper the squash, and place flat side down on a baking sheet lined with parchment paper. Roast for about 30 minutes, stabbing with a fork occasionally.
Meanwhile, put all the sauce ingredients in a blender and chop and weigh the veggies and chickpeas.
Place the vegetables and chickpeas in a large cast iron pan, or casserole dish and set aside.
When the butternut squash is ready and cooled a little, add the cooked butternut squash to the blender.
Blend the sauce until smooth.
Pour the sauce over the veggies, stir to combine, and bake in the oven for about 30 minutes, covered with a lid.