Wash and skin potatoes. Cut into large chunks and place them into the bottom of the Instant Pot.
Cut open Butterball turkey breast bag and rinse breast under warm water until you can remove the gravy pouch. Do not cut the inner netting of the breast, it will help it keep it's shape. Run gravy pouch under warm water.
Add gravy packet that comes with the breast and turkey broth to the bottom of the pot with the potatoes. Place in high legged trivet.
In a small bowl combine all of the spices, lemon juice, and olive oil to make a rub. Either brush or rub spice mixture onto all sides of the turkey breast.
Place the breast on the trivet and top with butter slices.
Close and seal Instant Pot. Set for 50 minutes on manual high pressure. When timer is done, allow for a full natural pressure release.
Remove breast and set aside to rest. Scoop out potatoes into a large bowl straining out as much juice as possible, and set aside. I use a slotted spoon for this.
Remove about ½ cup of liquid from the Instant Pot and mix with cornstarch. Note: if you like a thicker gravy you can mix in another tablespoon of cornstarch. but the gravy will thicken as it sits. Turn Instant Pot onto saute and add cornstarch mixture back to pot. Heat until boiling and stir constantly. Turn pot off and continue to stir for another minute. Then let it sit for a minute or two to thicken.
While gravy is resting, mash potatoes. Add salt and pepper to taste. BE CAREFUL with the salt because the potatoes are cooked in a salty broth. Cut up turkey breast and enjoy!