Step 1Preheat oven to 160°C. Heat olive oil in a large flameproof casserole dish over medium-high heat. Add beef, brown all over; remove.
Step 2Add onion and garlic to the dish; cook, stirring, for 2-3 minutes, or until onion softens. Add seasoning and cook, stirring, for about 1 minute. Stir in zest, stock and tomatoes with 3/4 cup water; bring to the boil.
Step 3Return reserved beef to dish, cover and cook for 2 hours, then remove lid and cook for a further 1–1 1/4 hours, or until beef is very tender. Use 2 forks to shred beef.
Step 4Divide quinoa, black beans, tomatoes, avocado and beef among 6 serving bowls; top with coriander and jalapeños.