Place all ingredients, except for the kidney beans and the spinach, into your pressure cooker and stir to combine. Lock the lid and cook on high for 20 minutes. Release pressure naturally for 10 minutes before performing a quick release for the remaining pressure. Stir in the kidney beans and spinach until the leaves are wilted. Add salt and pepper, to taste.
Slow Cooker Directions:
Use a 6-quart slow cooker. Add all ingredients except for the spinach leaves to the pot. Cover and cook on low for 6-8 hours, or on high for 4 hours. Stir in spinach leaves until wilted. Add salt and pepper, to taste.