2 medium lemons
3 tablespoons finely chopped shallots
2 tablespoons Dijon mustard (choose one whose flavor you like on its own — we used Maille)
2 tablespoons drained capers, finely chopped
1/2 teaspoon Maldon or another flaky sea salt
1/2 teaspoon superfine sugar
1/4 cup extra virgin olive oil

Segment the lemons over a bowl to catch the juices. Set aside. Squeeze the juice from the membranes into a separate bowl, add the rest of the ingredients, and stir well. Add the lemon segments and toss gently to coat them without breaking them up. Use straightaway or chill in the fridge, covered, for up to an hour. Note: To segment the lemons: Use a sharp knife to cut off just enough of the fruit’s top and bottom to expose a full circle of the flesh on either end. Stand the lemon on one of its ends, place your knife point at the seam where the fruit meets the pith, and use a gentle sawing motion to cut away a wide strip of pith and skin, following the curve of the fruit from top to bottom. Repeat the process until all you have left is a nice, round, naked fruit. If you’ve missed any white pith, trim it off. Make a cut down either side of each segment, right against the membrane, and gently pry out each segment, one at a time. Flick out any seeds, and set the segments aside in a bowl, reserving the juicy membranes.