Coarsely crush peppercorns in a pepper mill, a mortar and pestle, or in between two layers of parchment paper with a mallet.

Cut beef into 1 ?" cubes and season generously with crushed peppercorns and salt to taste.

Set the Instant Pot to the Saute setting on medium heat and add a tablespoon of olive oil. Once hot, add a single layer of beef cubes and cook until seared on both sides. Repeat with remaining beef. Set beef aside.

Add minced garlic and thyme to the pot and cook for 1 minute. Add cognac and scrape up any tidbits from the beef. Add flour and stir. Slowly whisk in beef broth until well blended.

Add potatoes, beef, and salt to taste. Place the lid on the Instant Pot and seal the vent. Set to Manual and the cooking time to 32 minutes. Once done, allow it to naturally release.

While the beef and potatoes cook, add ? cup of olive oil and sliced shallots to a saucepan over medium-high heat. Cook for 2-3 minutes, until onions are golden. Remove onions with a slotted spoon and place on a paper towel-lined plate. Discard the oil and wipe out the saucepan.

Using the same saucepan from the onions, add cognac and beef broth. Simmer until the liquid is reduced by half. Allow to slightly cool.

Add whipping cream to a medium-sized bowl and whisk for 1-2 minutes until it becomes frothy on top. Whisk the cognac and beef into the whipping cream. Add black peppercorns, Dijon mustard, and salt to taste, continuing to whisk.

Add ? of the creamy peppercorn sauce to the soup. Use the remaining sauce to drizzle on top of each individual serving as well as crispy onions.