Add the chopped cabbage, chicken broth, diced tomatoes, Italian seasoning, salt, pepper, and bay leaf to the Instant Pot inner pot. Stir gently to combine the ingredients.
Place the browned sausage back into the pot on top of the vegetables. Do not stir again.
Secure the lid and set the vent to Sealing. Select Manual or Pressure Cook on High pressure for 8 minutes.
When the cooking cycle finishes, allow a Natural Pressure Release (NPR) for 10 minutes. After 10 minutes, carefully move the valve to Venting to release any remaining pressure (Quick Release).
Remove and discard the bay leaf. Stir the soup well. Taste and adjust salt and pepper if needed. Serve hot.
Notes
For a low-carb option, skip adding potatoes or rice. This soup is naturally low in carbohydrates.
If you prefer a creamier texture, stir in 1/2 cup of heavy cream after the pressure release step.
You can use smoked sausage, kielbasa, or even spicy Italian sausage for different flavor profiles.
If you want to add potatoes, cut 2 medium potatoes into 1-inch cubes and add them with the broth. Increase the cook time to 10 minutes at High Pressure.