1 The day before, squeeze 8 tablespoons of lime juice and combine with 4 tablespoons of water. Pour mixture into ice cube trays and freeze.
2 The day you plan to serve the dish, whisk together tomato juice, Worcestershire sauce, Tabasco and salt and pepper to taste. Cover and refrigerate.
3 Peel onion and chop finely. Squeeze lemon. Combine 1 tablespoon lemon juice with salt, pepper and diced onion. Drizzle in some olive oil.
4 Halve avocado and remove pit. Scoop out avocado flesh and cut into wedges.
5 Add avocado to onion mixture and gently stir to combine the ingredients. Set aside for 15 minutes.
6 Toast bread. Rinse cilantro, pat dry and chop leaves.
7 Spoon avocado onto toast and sprinkle with cilantro.
8 For decoration, lightly moisten the rims of 2 small glasses using a wedge of lime and dip rims in salt. Place 2 lime ice cubes inside the glasses and fill with tomato juice. Serve with the avocado toast.