1 tbsp (15 mL) balsamic vinegar
1 tbsp (15 mL) vegetable oil
2 cloves garlic, minced
1/2 tsp (2 mL) dried thyme
1/2 tsp (2 mL) dried oregano
1/2 tsp (2 mL) grated lemon rind
1/2 tsp (2 mL) cracked peppercorns
1/2 tsp (2 mL) salt
3 lb (1.4 kg) Sirloin tip oven roast
1/4 cup (50 mL) all-purpose flour
2-1/2 cups (625 mL) beef stock
2 tbsp (25 mL) tomato paste
In small bowl, combine vinegar, oil, garlic, thyme, oregano, lemon rind, peppercorns and salt; rub all over roast.
Place on rack in roasting pan; add 1-1/2 cups (375 mL) water to pan. Roast in 500°F (260°C) oven for 30 minutes. Reduce heat to 275°F (140°C); roast until thermometer inserted in centre registers 150°F (65°C) for medium-rare, about 1-1/4 hours.
Transfer roast to cutting board; tent with foil and let stand for 10 minutes before thinly slicing.
Meanwhile, skim off any fat from pan juices. Sprinkle with flour; cook over medium heat, whisking, for 1 minute. Whisk in stock and tomato paste; bring to boil. Reduce heat and simmer until thickened, about 3 minutes.
Remove half of the beef slices and 1/2 cup (125 mL) of the gravy; let cool for 30 minutes. Wrap and refrigerate separately for up to 24 hours.