I got this wonderfully comforting recipe from Nigella Bites, and it is a delicious way to use up leftover mashed potatoes. She suggests using canned salmon instead of fresh, so I bought a can of the stuff for the first time tonight.
Man, it was a great deal! 14.5 ounces of wild salmon for $1.50. I'm not suggesting that it's an adequate substitute for a freshly grilled salmon filet, but if you need some cheap protein and a quick hit of omega-3 fatty acids I don't know if it can be beat for the price.
Nigella uses matzo meal in place of bread crumbs to fry these fish cakes, but I used panko instead since I had it in my cabinet.
For the fish cakes:
1.5 to 2 cups cold mashed potatoes
14.5 ounces canned salmon, drained
1 tablespoon unsalted butter, melted and cooled (optional--only use if the mashed potato hasn't got any butter in it)
1 pinch cayenne pepper
Grated zest of 1/2 lemon
Salt and pepper (season cautiously--remember that the canned salmon will be salty and the potatoes have already been seasoned!)
For coating and frying:
3/4 cup panko breadcrumbs or medium grain matzo meal
scant 1/4 cup unsalted butter
2 tablespoons vegetable oil
In a large bowl, mix together all of the fish cake ingredients with clean hands.
Cover a baking sheet with plastic wrap. Form palm sized patties of the mixture, and place on the baking sheet. I got 7 cakes out of my mixture, but I think it will vary on how much potato you have. Set the baking sheet in the refrigerator and leave the cakes to firm up for however long you can wait--at least 20 minutes. To save time in the evening, you can mix up the patties first thing in the morning and leave them to sit in the fridge all day until dinner time.
Even with this time in the fridge, you will have to handle the fish cakes very delicately during the dipping and frying process. I had one fall apart on me!
Beat the eggs in a shallow bowl and spread out the breadcrumbs on a plate. Dip each fish cake into the egg and then into the breadcrumbs, coating evenly. Warm the butter and oil in a large pan over medium high heat. When the butter is melted and starts to fizzle, fry the fish cakes on each side until golden brown and the centers are warmed through.