Put butter and oil into your foodi and set pot to saute setting.
Season beef with salt and pepper liberally. When butter is melted add roast into pot and sear on each side until well browned. About 1-2 min. on each side. Turn pot off.
Remove meat and deglaze pot by adding a bit of your broth and scraping bits of stuck on meat off bottom of your pot (so you avoid the WATER or burn notice)
Set to saute again, add your onions into pot until they are softer and translucent, then add garlic and cook for 1 more minute. Turn off pot!
Put beef back into your pot with onions, worcestershire sauce, and pour broth on top.
Close pressure cooker lid (one that is not attached) and steam valve and set to high pressure for 50 minutes.
Then allow steam to naturally release when done. Lift lid when steam is gone and add vegetables.
Close lid again and set on high for 6 minutes. Then do a quick release. Lift lid and remove beef.
Allow to rest for 5 minutes before slicing or shredding to serve. If you want to make gravy out of drippings in the pot set to saute again at the end once food is removed. In a bowl whisk 3 tbsp cornstarch with some hot liquid from pot. Whisk until smooth and add back in. Allow to bubble and thicken.