Add all ingredients EXCEPT the shrimp and rice to the slow cooker. Stir to mix well.
Cook HIGH 2-3 hours or LOW 4-6 (add an hour or so if you’re using dark meat).
Stir in shrimp and cauliflower rice and cook an additional 5-20 minutes or until shrimp are no longer pink. Remove bay leaves before serving.
Instant Pot
Turn on the IP and select Sauté. Once hot, add oil.
Add bell pepper, onion, and celery to the pressure cooker and cook 3-5 minutes or until soft. Pour diced tomatoes and broth into the Instant Pot. Deglaze the bottom of the pressure cooker by scraping all the bits off with a wooden spoon.
Close lid and seal valve. Set high pressure and cook for 5 minutes (7 minutes if using chicken thighs). Quick release pressure.
Stir in cauliflower rice and shrimp. Turn off the pressure cooker and put the lid back on. Let the food sit 10-15 minutes or until cauliflower is soft and shrimp is pink. Remove bay leaves before serving.