Roast Beef with Marsala Gravy

INGREDIENTS

• Freshly ground black pepper
• 1 1/2 tablespoons kosher salt
• 1 (3 pound) boneless beef roast, such as bottom round or rump roast
• 1 teaspoon all-purpose flour
• 4 cloves garlic, cut into thick slivers
• 1 1/4 cups water
• 1 cup beef broth
• 3/4 cup Marsala cooking wine
• 1 tablespoon butter
• Sprig fresh rosemary