In place of dry vermouth in the yoghurt dressing, use 1 teaspoon dry white wine or 1 teaspoon orange juice. Dry vermouth has a slightly "herby" taste and aroma.
Finely shred 1 medium head iceberg lettuce. Slice 3 celery stalks into thin strips and finely grate 2 medium carrots. Combine in a serving bowl.
Whisk 2 tablespoons olive oil, 3 tablespoons lemon juice, 1 teaspoon whole-grain mustard, 1⁄4 teaspoon sugar until combined; add salt and white pepper to taste.
Pour over salad and stir to combine.
Cut 100 g smoked salmon into strips and place on top of salad. Garnish with lemon slices and celery leaves.