Salmon Cakes with Sorrel Sauce

Name: Salmon Cakes with Sorrel Sauce
Ingredients: 1 pound cooked or canned salmon, flaked; 2/3 cup cooked potato, from Crisp Potato Skins; 2 large eggs, lightly beaten; 3 scallions, white and pale-green parts only, finely chopped; 3/4 teaspoon coarse salt; Freshly ground pepper, to taste; 4 tablespoons extra-virgin olive oil, plus more as needed; 3/4 cup heavy cream; 2 cups thinly sliced fresh sorrel leaves (4 ounces); 1/3 cup fresh flat-leaf parsley leaves; 2 teaspoons fresh lemon juice