First, dice up your bacon, celery, onions, and garlic. If you are using Italian sausage, either slice it or crumble it. I like to use crumbled sausage instead of slices so we remove it from the casing.
Next, set your Instant Pot to the sauté function. Once it is hot (it won't take long), add half of the olive oil (1 tbsp) and swirl it around to coat the whole bottom of your Instant Pot.
2 tablespoons extra virgin olive oil
Now, cook the Italian sausage to about 80/90%, then remove it from the pot and drain the grease.
½ pound Italian sausage
After removing the sausage, add the remainder of the olive oil (1 tbsp).
2 tablespoons extra virgin olive oil
Next, add the bacon and cook until it is slightly crispy.
4 slices bacon
Then add the diced onion and celery. Cook until the onion is translucent.
1 onion, 2 stalks celery
Now, add the garlic and spices and mix everything together.
3 garlic cloves, 1 teaspoon dried oregano, 1 teaspoon kosher salt, ½ teaspoon black pepper, ¼ teaspoon crushed red pepper flakes
Next, add the chicken broth, diced tomatoes with their juices, ditalini pasta, cannellini beans, cooked Italian sausage, and parmesan cheese rind if you are using one. Mix everything together.
1 28oz can diced tomatoes with juice, 3 cups chicken broth, 1 cup ditalini pasta, 1 14.5 oz can cannellini beans, 1 parmesan cheese rind
Finally, put the lid on your Instant Pot and make sure the vent is closed. Turn the Instant Pot saute mode off and switch it to "Manual Mode" at high pressure for 4 minutes.
It will take about 15 minutes for the Instant Pot to come to pressure. It will then count down 4 minutes. When the 4 minutes is up, turn the Instant Pot off and let it release naturally for 5 minutes. Then, quick release the remaining pressure. (I use a 6 quart Instant Pot and this amount of liquid has never been a problem as far as exploding with a quick release. I wouldn't quick release with a 3 quart Instant Pot.)
Once all the pressure is released, open the lid. Your soup will be done!