The recipe
Slice 4 large tomatoes in half, put them on a baking sheet. Trickle over a little olive oil, season with black pepper, then add an anchovy fillet to each one. Cook under an overhead grill until hot and lightly toasted. Peel a cucumber, slice down its length then scrape out the seeds with a teaspoon and discard. Make a dressing for the cucumber by pouring 5 tbsp of olive oil into a blender or food processor, adding the leaves from three or four large sprigs of tarragon and a few leaves of parsley. Blitz until you have a bright-green dressing.
The trick
Ripe sweet tomatoes are best for this, to balance the salty qualities of the anchovy. You don't need to put salt on the tomatoes, the anchovy is salt enough. Use good sourdough and flavoursome olive oil.
The twist
Use tarragon or chervil in place of the basil. Serve the whole lot as a filling for a warm pitta, tipping the cooked tomatoes and crunchy cucumber into the toasted pitta pockets. Add a crumbling of feta cheese and a few torn basil leaves.
Email Nigel at nigel.slater@observer.co.uk
'Blitz the tarragon and parsley until you have a bright-green dressing': Nigel Slater on his baked tomatoes with anchovy. Photograph: Jonathan Lovekin for the Observer