For the Lemon Mayo:
2 large organic egg yolks
Zest of 1 lemon plus 2 tablespoons lemon juice
2 teaspoons Dijon mustard
1 cup grapeseed oil
1 can sustainable tuna, drained
2 small ribs celery from heart with leafy tops, finely chopped
1 large shallot, finely chopped
3 tablespoons tarragon, chopped
Juice of 1 lemon
1/3 cup Lemon Mayo (store any unused mayo in the fridge)
Black pepper, to taste
Toasted baguette and bibb lettuce, shaved radishes and chopped cornichons, to serve
For the mayo, place egg yolks in a mixing bowl with the lemon zest and juice, and Dijon mustard. While whisking, slowly stream in the grapeseed oil until emulsified.
In another bowl, flake tuna and combine with celery, shallots, lemon juice, 1/3 cup of the lemon mayo and black pepper. (Store remaining lemon mayo in the fridge or use for Chicken or Fish with Lemon-Parm Crust.)
Fill baguette with lettuce and tuna salad, radishes and cornichons.