Take brisket out of the fridge 30 minutes before cooking. Season brisket with salt and pepper. Place in a 120ml (12cm depth) gastronorm.
Heat oil in a large saucepan over medium high heat. Add onion, garlic and chilli. Cook for 4-5 minutes or until onions start to soften. Add coriander, cumin and paprika, continue cooking for 1 minute, stirring. Reduce heat, add tomatoes, apple cider vinegar, chipotle sauce and stock. Once simmered, pour over brisket.
Cover tightly with baking paper and foil, place in oven for 10-12 hours at 90°C to 92°C, 60% steam, 40% dry heat.
Remove from oven, take beef out of gastronorm and set aside to rest. Pour sauce into a saucepan. Allow to cool and fat to rise to the top. Remove fat. Place on a medium-high heat and bring to the boil. Reduce slightly.
Carve brisket thinly and coat with reduced sauce.
To assemble arepa: fill pocket with avocado, black beans, brisket, red onions, capsicum, plantains, coriander and mayonnaise.