For sauce gribiche, cook egg in boiling salted water until hard-boiled (10 minutes), drain and refresh under cold running water. Peel, finely chop and set aside. Meanwhile, cook garlic in a small saucepan of boiling water until tender (4-5 minutes), strain and mash with a fork until smooth. Transfer to a bowl, add yolk, mustard and vinegar and whisk to combine. Add oils in a thin steady stream, whisking continuously until thick and emulsified and thinning with a little hot water if necessary. Stir through cornichons, capers, tarragon and hard-boiled egg, season to taste and refrigerate until required. Makes about 1 cup.
Preheat oven to 120C. Spread baguette slices on an oven tray, drizzle with a little olive oil, season to taste, bake until light golden and crisp (10-12 minutes), cool to room temperature. Croûtons will keep for 2 days in an airtight container.
Combine cos and rocket in a bowl with vinegar and remaining olive oil, season to taste. Place dollops of sauce gribiche on serving plates, arrange lettuce mixture on top and drape each salad with three anchovies. Coarsely crumble over croûtons, scatter with chives and serve.
This recipe is from the January 2011 issue of Australian Gourmet Traveller.