Put the corned beef into the pressure cooker with the fat cap facing up. Add the wine and the spices from the packet. Cover and set steam valve to sealed position. Cook on high pressure for 60 minutes. Let the pressure release naturally for 15 minutes, then release the remaining pressure manually.

Open the lid. Drop the potatoes and carrots into the liquid that surrounds the beef. Lay the cabbage wedges on top. Cover and set steam valve to sealed position. Cook on high pressure for 15 more minutes.

Let the pressure release naturally for 10 minutes, then release the remaining pressure manually. Open the lid. Using tongs, remove the cabbage wedges, potatoes and carrots to a serving platter.

Heat the broiler to high. Stir together the mustard and honey in a small bowl. Using tongs, remove the corned beef from the pressure cooker and put it on a foil-lined sheet pan. Spread the honey-mustard all over the top and sides of the beef and place it under the broiler; cook until the glaze bubbles and caramelizes in spots, about 3 minutes.

Let the corned beef rest for 5 to 10 minutes then slice it against the grain into ½-inch slabs. Place the beef slices on the serving platter alongside the vegetables and drizzle everything with a little bit of the cooking liquid. Taste the vegetables, and season them with flaky sea salt, if necessary. (The beef will not need to be seasoned with salt.) Season the beef and vegetables to taste with black pepper. Serve with Dijon mustard.