Have leftover mashed potatoes? It's so easy to turn them into mashed potato cakes! Crisp on the outside and warm and creamy in the center, these feature a secret trick for never-dry consistency and an extra boost of flavor.
As a small household, we're always left with leftover sour cream mashed potatoes. Not that I'm complaining! We love those potatoes.
Beyond a simple reheat, I sometimes like to get fancy with leftover mashed potatoes and turn them into potato cakes. With some adjustments I treat prepared mashed potatoes almost as a fritter base, adding flour, eggs, and spices before pan-frying. And whereas I go with Parmesan for zucchini fritters, cheddar is my pick here.
This recipe calls for two cups of mashed potatoes, but the ingredient measurements are easy to halve if you have left a smaller portion.
Why You'll Love Mashed Potato Cakes
- The flavor. Not only does grating the onion provide lots of moisture, but it adds a background flavor that when combined with the cheese, reminds me of smooth pierogi filling. YUM.
- The texture. I tested this recipe with two other cooking methods - baking and air frying - and found them both to produce mashed potato cakes lacking in pizzazz. Pan frying reliably achieves that satisfyingly golden-brown and crisp outer texture.
- It keeps things fresh. Leftovers can get a little one-note (especially Thanksgiving leftovers), so using mashed potatoes as an ingredient in something else shakes things up.
Before Beginning: Consider your particular mashed potatoes when preparing this recipe. If they're on the softer side to begin with you may need an extra sprinkle or two of flour. Vice versa if they're firmer. If they're heavily seasoned, pull back on additional salt.
- Mashed potatoes: Any basic cold mashed potatoes will do, though if they're already flavored with herbs, bacon, cheese, etc.? Even better! This recipe is great for the occasions we have roasted garlic mashed potatoes on hand.
- Flour: Some flour is necessary to provide structure in mashed potato cakes, but it's fine line between using just enough and too much, which can lead to drier cakes and an unappealing flavor.
- Eggs: To help bind all of the ingredients together.
- Onion: Grating the onion (versus dicing it) is a difference maker. Grating an onion releases a ton more moisture and allows the flavor to permeate the entire filling (it doesn't overpower). White or yellow onions are fine, and use care when grating as it can get slippery.
- Cheese: Either grated or small-dice block cheese is fine.
- Hot sauce: This provides more flavor than heat, though increase the amount if you'd like some spice.
- Seasonings: I like salt, pepper, and garlic powder, but add whichever ones you like.
- Olive oil: For pan frying the potato cakes.
- Mix - Combine all ingredients (except for the oil) in a mixing bowl.
- Shape (optional) - This is a soft and sticky batter that isn't easy to shape into patties. If you really want to, shape and place on a sheet of parchment paper. Lightly wet your palms to reduce the sticking, and use a greased spatula for transferring to the pan.
- Pan Fry - Heat oil sufficiently, then transfer pre-shaped patties to the pan or simply scoop batter and flatten into cakes with a spatula. Cook for several minutes per side, until both sides are a deep golden-brown.
- Drain - Transfer patties to a paper towel-lined plate while you cook the rest of the batter.
Expert Tips and Tricks
- Avoid adding too much flour. The soft, semi-sticky nature of the mashed potato cake batter means that the cakes will not be precisely round and totally mess-free to handle. That's a given for this type of recipe. I've tried to see if this could be improved upon but found test batches with extra flour did not do much to alleviate this, and only served to dilute the onion and cheese flavor and reduce the inner creaminess.
- Shaping the cakes. If you'd rather not pre-shape cakes on parchment, you can scoop the batter into the hot pan (like fritters), then flatten it into a round shape with a spatula.
- Don't use a large pan. While it's tempting to use a large skillet to cook more cakes at one time, the oil has more space to run off to. Use a smaller skillet to more effectively pan fry the cakes.
Frequently Asked Questions
While it's possible, I did not find these potato cakes to be as satisfying when air fried and would recommend pan frying. If trying in the air fryer, be cautious as the soft batter can sink down into grid-style baskets (use a trimmed piece of parchment paper or appropriate liner for your air fryer model). Spray cakes generously with olive oil spray to coat the surface and promote crispness.
Meat: Leftover cooked and crumbled bacon or small-diced ham can be added to the batter. Cheese: Try out Parmesan, Provolone, or smoked gouda. Herbs: Fresh chives or dill.
These make a great appetizer or small dish served hot alongside sour cream for dipping.
More Ways to Use Up Leftovers
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Leftover Mashed Potato Cakes
- 2 cups prepared mashed potatoes cold
- 2 large eggs
- ½ cup shredded or small-diced cheese (like cheddar)
- ¼ cup grated onion
- ½ teaspoon hot sauce
- ½ teaspoon garlic powder
- ¼ teaspoon kosher salt
- ¼ teaspoon ground black pepper
- 1 cup all-purpose flour
- 3 Tablespoons olive oil for pan frying, more as needed
- Stir together all ingredients (except for the olive oil) in a mixing bowl until evenly combined.
- If you want to pre-shape the mixture into patties, do so now and place them on a parchment paper-lined plate. Bear in mind the batter will be soft and fairly sticky (messy), so you may wish to skip shaping and simply scoop batter directly into the pan during the next step.
- Heat olive oil in a medium nonstick skillet over medium-high heat. Once the oil is sufficiently hot, add pre-shaped cakes to the pan (use a greased spatula to transfer) or use a cookie scoop to form heaps of batter in the pan, then flatten with the back of a wooden spoon or spatula.
- Cook for 3-4 minutes, or until the bottom side is a deep golden-brown. Flip each potato cake over and pan fry for a few more minutes, until the other side is also golden-brown. Adjust the heat as needed so the cakes don't overly brown before heating throughout. Remove to a paper towel-lined plate to drain.
- Repeat with the remaining batter, adding additional oil to the pan as needed. Serve warm with optional sour cream for dipping.
- Adjust for your potatoes: If your mashed potatoes are on the softer side to begin with, you may need an extra sprinkle of flour. Vice versa if they're quite firm. If they're heavily seasoned already hold back on the additional salt.
- Other ingredients to add: Cooked and crumbled bacon, small-dice ham, fresh herbs like chives or dill, green onions, other cheese varieties like Parmesan, Provolone, or gouda.
- Grating onion: Use caution as it can get slippery (I wear a cut-resistant glove). It's helpful to do this on a cutting board with outer grooves as a lot of moisture is released.
- Nutrition: Hard to estimate due to ingredient variability, frying oil left behind, etc.
Nutritional information is provided as an estimate. As it can vary due to many factors (brands used, quantities, etc.), we cannot guarantee its accuracy.Food Safety and Nutrition Disclaimer