Sardine and Watercress Salad with Shredded Potato Cake

• 1 tablespoon white-wine vinegar, or to taste
• 1 tablespoon Dijon-style mustard, or to taste
• 1/4 cup olive oil
• 1 tablespoon water
• a 1/2-pound russet (baking) potato
• 1 tablespoon unsalted butter
• 1 small bunch of watercress, rinsed, spun dry, and coarse stems discarded (about 3 cups)
• 1/2 red onion, sliced thin, separated into rings, and soaked in ice water to cover for 30 minutes
• a 3 3/4-ounce can brisling sardines packed in oil, drained well

1. In a small bowl whisk together the vinegar, the mustard, and salt and pepper to taste, add the oil in a stream, whisking, and whisk in the water.
2. Peel the potato, grate it coarse, and squeeze it between several thicknesses of paper towels to remove any excess moisture.
3. In a non-stick skillet measuring 6 inches across the bottom heat 1/2 tablespoon of the butter over moderately high heat until the foam subsides, add half the potato, tamping it down with a spatula, and cook the potato cake, shaking the skillet frequently to keep the potato from sticking, for 6 minutes, or until the underside is golden and crisp.
4. Turn the potato cake, cook it for 6 minutes more, or until the underside is golden and crisp, and transfer it to a plate.
5. Make a second potato cake in the same manner with the remaining butter and potato and transfer it to another plate.
6. In a bowl toss the watercress with 3 tablespoons of the dressing and spoon the remaining dressing around the potato cakes.
7. Arrange the onion, drained well, the watercress, and the sardines decoratively on the potato cakes.

whitewine vinegar, mustard, olive oil, water, potato, unsalted butter, red onion, brisling sardines packed

Taken from www.epicurious.com/recipes/food/views/sardine-and-watercress-salad-with-shredded-potato-cake-11747 (may not work)