Put the 2 cups of dry navy beans and sea salt in a medium bowl with warm water to cover by 2-3 inches. Let the beans soak for 8-10 hours, then rinse and strain and set them aside until they are ready to add to the IP.
Turn the Instant Pot on to “Saute,” add the butter to melt, and then add the onion, carrot, and celery with a pinch of sea salt. Saute for 5-7 minutes until fragrant and soft.
Add the garlic, paprika, dill, and red pepper flakes, stir and saute for 1 minute. Turn the IP to “Off.”
Pour the drained beans and bone broth into the IP, stir to combine, put the IP lid on, and turn the valve to closed.
Turn the Instant Pot on to “Soup,” and leave the time at 30 minutes. The Instant Pot will automatically turn on, and will take about 10ish minutes to come to pressure (depending on how cold your broth is) before counting down the 30 minutes. When the time beeps that the 30 minutes is done, turn the Instant Pot “Off,” and leave the valve closed and lid on to naturally let the pressure release. This gives the beans time to finish cooking and locks flavor in. After about 15 minutes, you can open the lid.
Ladle out about half the soup, puree it in a blender or with a hand-held immersion blender, and return the pureed soup to the pot. Add the lemon juice and kale to the soup and stir. The heat from the soup will wilt the kale, and you can season your soup with salt and pepper to your taste.