For the spice packet: Place pickling spices, juniper berries, and bay leaves into a cheesecloth bag and place into the inner liner of the Instant Pot or pressure cooker.
Place the beef into the inner liner of the instant pot. Add onions, carrots, ginger, sugar, salt, and pepper. Pour over the red wine vinegar and chicken broth.
Set the Instant Pot at High pressure for 40 minutes. When cook time is complete, let the pot sit undisturbed for 10 minutes, and then release all remaining pressure.
Open the lid and remove the beef to a serving tray. Cover with foil and let it rest. Discard cheesecloth bag.
Add in in crushed gingersnaps (if using), sour cream (if using) and mustard. Use an immersion blender to blend the vegetables until a rough sauce forms. Pour over the meat and serve.
If you can't find pre-mixed pickling spices, it usually is a loose combination of mustard seeds, allspice berries, whole coriander seeds, bay leaves and cinnamon. Honestly, just throw some of those in there and call it a day.