Add the olive oil to your instant pot. Set to sauté and allow the oil to get hot. Whilst the oil is heating, roughly slice the steak into half inch strips. Carefully add the steak strips to the instant pot. Using the sauté function, brown the beef all over.
Whilst the steak browns, thinly slice the onion and 1 large garlic clove. Add the sliced onion and garlic to the instant pot with the steak. Stir well to combine. Sweat the onion and garlic until tender and lightly golden. Take care not to burn the onion or garlic as this will impair the flavor of the soup.
Whilst the onion cooks, dice the cauliflower into bite sized chunks. Add the cauliflower pieces and the stock to the instant pot and stir well to combine. At this point you may season with salt and pepper if you wish. This will depend on the level of seasoning already in your stock. You may also use chicken or vegetable stock if preferred but be sure to adjust your macros for any changes.
Place the lid on the instant pot with the valve set to ‘sealing’ and set to high pressure. Set the time for 8 minutes. After this time, do a quick release to release the steam. Once the pressure has been released and it is safe to do so, open the lid and portion out the soup for serving. Taste and adjust seasonings if required.