STEP 1 Cut the beef into about 1 inch cubes. In a large bowl coat the cubed beef with the flour and some salt and pepper. Shake off the excess. Set aside and prepare the vegetables. Chop the shallots, cube the potato into quarters and slice the carrots (or leave whole for presentation).
STEP 2 Heat oil in an Instant Pot or dutch oven and add in the beef chuck. Brown on all sides.
STEP 3 Add in the shallots, potatoes and tomato paste and stir. Pour in the broth and Pat Thai Sauce, scraping the bottom of the pan to remove any caramelized bits. If using an Instant Pot, cook on high pressure for 25 minutes. If cooking the beef in a dutch oven, simmer for 4-6 hours.
STEP 4 In the Instant Pot, after 25 minutes, release the pressure and add in the carrots. Cook an additional 3 minutes on high pressure. The carrots should be tender and the beef fork tender. If you're cooking in a dutch oven, you'll add in the carrots about ¾ of the way into cooking. This will ensure the carrots don’t overcook.
STEP 5 Once the beef can easily be pulled apart by a fork, stir in the mustard and cream. Serve with chopped parsley and dill as garnish.