If you are soaking the butter beans before cooking, that will be your first step. To soak, place beans in a large bowl or pot and cover with about 2 inches of water. Once the beans have soaked and are rinsed, move on to the next step. If you chose not to soak the butter beans, move on the step 2.
Turn Instant Pot on the saute setting. Once hot add oil and saute sausage in Instant Pot for 3 - 5 minutes. Remove and set aside.
Add chopped onion, celery, green onion, and bell pepper to Instant Pot and saute until softened. Once softened add minced garlic and saute until fragrant.
Turn off saute setting. Add the chicken broth, butter beans, bay leaves, and cajun seasoning blend to the Instant Pot and lightly stir.
Cover with lid and to sealing. Set Instant Pot to Manual Setting on high pressure for 40 minutes.
After 40 minutes do a quick release. Once pressure has been released, remove lid and add sausage back to pot along with the butter and a few dashes of hot sauce and stir to combine and melt butter.
This last step is optional. After adding sausage, butter and hot sauce, change to saute setting and stir for about 5 additional minutes. I prefer really creamy butter beans and this last step does that.