Add the sliced sausage and cook until lightly browned, about 4 minutes. Remove the sausage with a slotted spoon and set aside.
Add the onion to the pot and cook until softened, about 3 minutes. Add the garlic and cook for 1 minute more until fragrant. Press Cancel.
Return the sausage to the pot. Add the chicken broth, chopped cabbage, diced tomatoes, Italian seasoning, salt, pepper, and bay leaf. Stir well to combine.
Secure the lid on the Instant Pot and set the vent to Sealing.
Select Manual/Pressure Cook (High Pressure) for 5 minutes.
When the cooking cycle finishes, allow a Natural Pressure Release (NPR) for 10 minutes before carefully moving the valve to Venting for a Quick Release (QR) of any remaining pressure.
Remove and discard the bay leaf. Taste and adjust seasoning if needed before serving.
Notes
For a low-carb option, skip adding potatoes or noodles.
You can use smoked sausage or Kielbasa for the best flavor.