Set Instant Pot to sauté, add coconut oil, onion, bell pepper, sweet potato and spices. Sauté for 5 minutes, stirring occasionally. Add cauliflower, sweet potato puree, tomatoes and stock. Add the Instant Pot lid and set to pressure cook on high for 5 minutes. Drain and rinse the heirloom beans. When the Instant Pot is finished cooking, allow to naturally release for 5 minutes, then carefully vent the remaining pressure. Remove the lid and add the heirloom beans. Let sit for 3-4 minutes, so the beans warm up, and serve.