Preheat your oven to 325°F (165°C). Gather your ingredients while the oven heats up.

Rub the beef eye round roast with olive oil, seasoned pepper, minced garlic, dried thyme, and salt.

Transfer the seasoned roast to a roasting pan, fat side up.

Roast the beef in the oven for 2 to 2.5 hours, checking for an internal temperature of 135°F (57°C) for medium-rare.

While the roast cooks, mix the horseradish sauce: combine sour cream, lemon juice, milk, prepared horseradish, Dijon mustard, salt, and pepper until smooth.

Once cooked, remove the beef from the oven, cover with foil, and let rest for 15 minutes.

Slice the roast against the grain and serve with horseradish sauce.