Preheat oven to 400 degrees. Wash and dry the potatoes, leaving the skins on. Slice into rounds and/or wedges and arrange on a baking sheet. Drizzle with olive oil, salt and pepper. Bake 20-25 minutes.

While the potatoes are cooking, make the vinaigrette: Whisk the lemon juice, tarragon, buttermilk, shallot, Dijon, fish sauce and honey in a small bowl. Slowly drizzle in the olive oil, whisking constantly until incorporated.

To prepare the tuna, heat 1 Tbsp. olive oil in a cast iron skillet over medium-high heat. Using your fingers, press a generous amount of salt and pepper into both sides of the tuna steak. Sear 3 minutes on each side. Remove to a cutting board and slice into strips.

To assemble, arrange the lettuce leaves in a large bowl or serving dish. Top with tuna, eggs, green beans, potatoes and olives. Drizzle with vinaigrette.