Preheat oven to 450 degrees F.
Lightly rub the salmon fillets with 2 teaspoons olive oil, and season the top with salt and pepper. Place on a baking sheet and roast uncovered in the oven until firm and cooked through, but still slightly rare in the center, 10 to 12 minutes. Remove from the oven and let cool slightly before gently lifting the skin from the bottom of each fillet. Set aside.
In a medium pot place the sliced potatoes and 1 teaspoon of salt. Cover with water by 2 inches, and bring to a boil. Reduce the heat and gently boil until the potatoes are just fork tender, about 7 minutes. Drain and rinse under cold running water. Drain and let cool.
In a bowl, whisk together the mustard and lemon juice. Slowly drizzle in the remaining 1/2 cup olive oil and whisk until an emulsion is formed. Whisk in the lemon zest, thyme, remaining 1/2 teaspoon salt, and cayenne.
In a bowl gently toss the cooked potato slices with some of the vinaigrette. Remove and arrange in a circular pattern on each of 4 plates. Top the potatoes with the cooled salmon fillets. Place the chopped artichoke hearts in the bowl and toss with the rest of the vinaigrette. Arrange the artichoke hearts around the salmon. Top the salmon with a little of the Choron Sauce.
Yield: 4 servings