Measure out and prepare all the ingredients. Heat an Instant Pot or pressure cooker on saute mode.

In the Instant Pot or pressure cooker, add avocado oil, diced celery, onion, and bay leaf. Saute until everything is tender.

Add in the oregano and chicken, then season with salt and pepper. Cook for about 5 minutes uncovered or until the chicken is browned on both sides.

Add the pumpkin puree, chicken broth, and pitted green olives. Stir well. Turn the pressure cooker on high, close the lid, and set to cook for 25 minutes.

In the meantime, make the cauliflower rice. Rice the cauliflower using a food processor - pulse florets of cauliflower until they resemble small crumbles. Work in batches if needed. In a pan over medium heat, melt the butter and add the riced cauliflower. Cook this for 8-10 minutes. Season with salt and pepper to taste.

Once pressure has released, open the lid and shred the chicken.

Put the shredded chicken back into the pot and squeeze the lemon into it. Stir well.

Serve the chicken with cauliflower rice. Enjoy!