In small bowl, combine butter, fresh minced herbs and garlic. Loosen turkey breast skin, rub some butter under skin, and all over the turkey breast. Season all over with salt and pepper.
Place metal trivet in Instant Pot insert and 1 cup of turkey stock. Place turkey breast, skin side up, on rack and seal pot. Cook on high pressure for 25 minutes. Let pressure naturally release for 15 minutes.
Release any remaining pressure and remove turkey breast to sheet pan. Turn on broiler and brown turkey for about 5 minutes, watching closely so not to burn.
Meanwhile, make the gravy. Pour turkey broth in measuring cup, you should have two cups. If not, add more stock to reach two cups. Turn on sauté setting and add butter or turkey fat to pot, melt, then sprinkle with flour. Whisk and cook for a minute or two until golden and flour taste is cooked off. Whisk in about a half cup of stock until smooth and thick, then gradually whisk in remaining stock. Cook a couple of minutes until thickened. Add optional dark soy sauce and taste for seasonings.
Remove bone from turkey. Slice turkey, plate on serving platter and serve with gravy on the side. Enjoy.