Set slow cooker to low or preheat the oven to 275°F.
Heat olive oil in a heavy bottom pan on stove top to a sizzle.
Liberally dust roast with cracked peppercorns and garlic powder.
Sear the roast on both sides to seal the juices.
Remove and transfer to slow cooker, or a deep covered casserole dish.
Mix all other ingredients together and pour into the casserole dish or slow cooker.
Add water so combined liquid just covers the top of the roast.
Cook for 6-8 hours in slow cooker, or 5-6 hours in oven until meat is fork tender.
Remove meat to serving platter.
Skim fat off surface of liquid, discard.
Thicken liquid with a roux for au jus or gravy.