Set pressure cooker to "sear", add chorizo, and press "start/stop". Sauté until browned. Remove; set aside.
Add onions, celery, and garlic. Cook until onions are translucent. Add squash, zucchini, sweet potato, red pepper flakes, sea salt, and fresh ground black pepper.
When fragrant, return chorizo to cooker. Pour in chicken stock.
Close and lock lid, set pressure cooker to "soup", adjust time to 5 minutes, and press "start/stop".
When done, quick release and make sure all pressure is released before opening lid.
Carefully open lid and garnish with cilantro leaves.