Cut the onions into large pieces and halve the garlic (precision isn't required here) and place them inside of the cooking pot of the Ninja Foodi. Add the salt and seasoning packet that came with the corned beef.

Add the brisket on top of the onions with the fat side facing up.

Mix the mustards and honey together in a small bowl. Add to the top of the corned beef brisket. And pour the Guinness around the beef brisket.

Install the pressure cooking lid and switch the vent to seal. Set the Foodi function to pressure cooker on HI and the time for 1 hour and 30 minutes. Press start. It takes about 10 minutes for the Foodi to come to pressure.

When the corned beef is near finished with cooking, prepare the vegetables. Cut up the potatoes and carrots into large pieces. Again, precision isn't required here. If they are cut up too small, they will disintegrate while cooking. Cut up the cabbage into quarters by cutting in half and then half again. Remove the core.

When the corned beef is finished cooking, quick release the pressure. Carefully remove the corned beef and place in a glass bowl with a lid to keep warm. Reserve the liquid inside of the Foodi cooking pot.

Add the carrots and potatoes to the cooking liquid. And place the cabbage pieces on top. Install the pressure cooker lid, set the vent to seal. Select the function to pressure cooker, HI. And the time to 3 minutes. Press start. Quick release the pressure when the cooking time is done.

Ladle a bit of the cooking liquid over the top of the corned beef if desired.

Serve and enjoy!