If using a pressure cooker that includes a saute function, set to saute and add 2 tsp olive oil. (If not, do this step on the stovetop). Saute mushrooms until softened, remove and set aside.

Season roast with salt and pepper. Add to pressure cooker still on saute function. Brown each side for one minute. Hit cancel to turn off saute.

Add broth and deglaze the pan. Add all other ingredients (onion, carrots, diced tomatoes and Italian seasoning).

Place lid on cooker and close valve to sealed. Cook on high pressure for 30 minutes. When finished, open valve to manually release pressure. Remove lid and move roast to cutting board. Add mushrooms to the cooker. Cut roast into cubes and return. Stir and replace lid until ready to serve.

Heat a skillet to medium high heat. Add 2 tsp olive oil and saute mushrooms for 2 minutes. Remove and refrigerate until later.

Season roast and add to heated skillet. Brown each side for one minute. Move to bottom of slow cooker. Add broth, tomatoes, carrots, onion and Italian seasoning. Cook on low for 6 hours.

Set slow cooker to warm. Remove roast to cutting board. Add sauted mushrooms to slow cooker. Cut roast into cubes and return to slow cooker. Allow to warm another 10-20 minutes and serve.