Heat the oven. Set your oven to 450°F. Place a large roasting pan in the oven to preheat while you prep. This helps the potatoes start crispy instead of sad.
Safety note: that pan will be screaming hot. Use good oven mitts and a clear landing spot on the counter.
Season the roast. Pat the beef dry. Mix 2 teaspoons of the kosher salt, 1 teaspoon of the pepper, garlic powder, and rosemary. Rub all over the roast with 1 tablespoon olive oil. Let it sit at room temp while you prep the potatoes, about 15 to 20 minutes.
Optional but helpful: If your roast is an uneven shape (common with rounds and sirloin tip), tie it with kitchen twine every 1 1/2 to 2 inches. It cooks more evenly and slices prettier.
Parboil the potatoes. Add potatoes to a pot, cover with cold water, and add 1/2 teaspoon kosher salt. Bring to a boil, then simmer 8 to 10 minutes until the outsides are tender but the centers are still firm. Drain well, then shake them in the colander for a few seconds to rough up the edges.
Toss the vegetables. In a bowl, toss the parboiled potatoes with carrots, onion, smashed garlic, 2 tablespoons olive oil, the remaining 1/2 teaspoon pepper, and the remaining 1/2 teaspoon kosher salt.
Pan size matters: For crisp potatoes, everything needs breathing room. If your roasting pan looks crowded, use two pans and rotate them halfway through.
Sear the roast (recommended). Heat a skillet over medium-high. If the pan looks dry, add 1 to 2 teaspoons neutral oil (avocado, canola, vegetable). Sear the roast about 2 to 3 minutes per side, until browned. Transfer to a plate.
If skipping the sear: no problem. Roast at 450°F for 25 to 30 minutes instead of 20 before lowering the temperature.
Start roasting (keep the potatoes dry). Carefully remove the hot roasting pan from the oven. Add the vegetable mixture and spread into an even layer. Nestle the roast in the center.
Optional note: If you prefer, you can set the roast on a rack so the vegetables underneath stay a bit crisper. Nestling it right in is totally fine, just know the veg directly under the roast will be softer (still delicious).
Important: do not pour broth over the vegetables. Liquid in the pan will steam and braise the potatoes, and we are here for crispy.
Roast hot, then lower. Roast at 450°F for 20 minutes (or 25 to 30 minutes if you skipped searing). Then reduce the oven to 325°F and continue roasting until the roast hits your target internal temp:
- 125 to 130°F for medium-rare
- 135°F for medium
Insert the thermometer into the center of the thickest part of the roast, avoiding big pockets of fat.
Plan on 55 to 75 minutes more for most 3 to 3 1/2 pound roasts, depending on cut and thickness. As a loose sanity check, many roasts land around 18 to 22 minutes per pound at 325°F, but shape, starting temperature, and oven quirks can swing it. Your thermometer gets the final vote.
Rest the roast. Transfer roast to a cutting board and tent loosely with foil. Rest 20 minutes. This is not optional if you like juicy slices.
Finish the vegetables. While the roast rests (it is out of the oven now), toss the potatoes and carrots in the pan.
If you want more crisp on the potatoes, bump the oven back to 425°F and roast the vegetables for 10 to 15 minutes. If the carrots or onions are already tender, pull them to a serving bowl and keep crisping just the potatoes. You can also slide the potatoes onto a second pan for maximum crunch.
Make the pan gravy. Pour any resting juices from the cutting board into the roasting pan. Place the roasting pan on the stove over medium heat (or pour drippings into a saucepan).
If the pan looks dry, add a splash of broth. If there is a lot of fat, skim some off, but keep a couple tablespoons for flavor. Add butter, then whisk in flour and cook 1 minute. Slowly whisk in pan juices plus enough broth to reach about 2 cups total liquid. Simmer until thickened, 3 to 6 minutes. Stir in Worcestershire if using. Taste and adjust salt and pepper.
Smoother gravy: strain before simmering, or strain at the end.
Slice and serve. Slice the roast against the grain. Serve with potatoes, carrots, onion, and a generous pour of gravy.
