Select the saute mode on the pressure cooker for medium heat. When the display reads HOT, add olive oil to coat the bottom of the pot. Add ground beef and cook for a few minutes until browned, breaking it apart as it cooks.
Add onions and carrots. Cook for about 5 minutes to soften, stirring frequently. Turn off the saute mode.
Add tomatoes (including liquid in the can), cabbage, beef stock, cauliflower, oregano, thyme, and salt. Briefly stir together.
Secure the lid and seal the vent. Cook at high pressure for 20 minutes, followed by a 15 minute natural release. Manually release remaining pressure.