Brown/sear the roast in the olive oil in a large skillet. You can also do this in the Instant Pot but I find my skillet works fast, and I will use it again anyway. So wash it out to have it ready.
Place the broth, Worcestershire sauce, pepper, garlic, Italian seasoning, onion soup mix and ranch dressing mix into the cooker pan. Whisk until blended. Do not add any salt. Add the browned roast in the Instant Pot with the cooking liquid.
Place lid on and set the vent to seal. Cook at pressure/high for 75 minutes and use the quick release.
Lift out the roast, set aside and tent with foil to keep warm.
Melt butter in the cleaned large skillet, whisk in the flour and add the cooking liquid and Kitchen Bouquet.
Keep heat on low and continue stirring until the gravy thickens; keep warm.
Peel and chop the potatoes and add to the cooker with salt and water.
Place the lid back on, set to seal, and cook at manual/at pressure/high for 7 minutes.
Use the quick release and drain potatoes.
Mash potatoes with soft butter and milk.
Chop or shred beef roast into bite sized pieces.
Place a slice of bread on the serving plate; top with a scoop of mashed potatoes.
Top potatoes with a serving of beef and cover all with gravy.