Slice a thin layer from the tough base of the lettuce and remove any wilted outer leaves, ensuring the lettuce remains intact. Slice the lettuce in half lengthwise. Mix a tablespoon of olive oil with a teaspoon of lime juice and brush all over the lettuce. Season with a pinch of salt and pepper.
Step 2
Heat a griddle pan over a high heat and place the lettuce in the pan cut side down. Cook for 3-4 minutes until well charred, turn and cook the other side for a further 3-4 minutes or until the lettuce is tender.
Step 3
Whilst the lettuce is cooking, add the avocado flesh to a food processor along with the remaining lime juice, zest, olive oil, garlic, salt and pepper. Blend until smooth.
Step 4
Spoon the avocado dressing over the charred lettuce.