how to thicken mashed potatoes

You’ve planned your family’s favorite dinner for tonight; baked salmon with creamy mashed potatoes. But disaster has struck, and the mashed potatoes are looser than you’d hoped for. In other words, runny! However, do not despair, because it’s not difficult to learn how to thicken mashed potatoes.

The humble potato is a delicious and nutritious vegetable. It can be cooked in many different ways, and can be served as a side dish accompanying the main course, or can even be a meal in itself if baked and filled with different types of fillings.

The type that always gets the most votes in our house is mashed potatoes. This food is so versatile and can be served as an accompaniment to so many different foods. It goes well with almost anything, is easy to make, and potatoes are usually quite budget-friendly. Therefore mashed potatoes make a frequent appearance on my table.

Although mash is relatively simple to prepare, there are things that can go wrong if you are not careful. One of the most common problems is that your mash turns out to be too runny or soggy. So what can be done to solve this? How do you thicken mashed potatoes?

Why Are Mashed Potatoes Sometimes Too Runny?

There are two reasons why your mash may be too runny. Let me elaborate.

  • Not Draining the potatoes properly

The first problem is that in order to cook the potatoes, you have to boil them in water. During the cooking process, the potatoes absorb a lot of the liquid.

It is essential that once cooked you drain the water from the potatoes very well. I advise pouring them into a colander and allowing them to stand for at least 15 minutes, giving them a good shake every 5 minutes, to allow all the water to drain fully. 

Once the water has drained completely, wrap the potatoes in a clean, absorbent kitchen towel and pat dry. This will help to remove the last remaining water and will avoid the mash being too runny.

  • Adding too much liquid

In order to get light, fluffy, creamy mash, most recipes advise adding either milk or cream, or sometimes both, to the potatoes when mashing them. Sometimes too much milk or cream can make the mash soggy and runny. 

The best way to avoid this happening is to add the liquid very gradually as you are mashing the potatoes until you get just the right creamy consistency.

If either of the above scenarios has caused your mash to be too runny, don’t toss it in the garbage. I can help.

There are two general ways to thicken mashed potatoes: either by adding a thickening agent or by removing surplus moisture. Let me share a few tricks with you to save the day.

How To Thicken Mashed Potatoes With Corn Flour Or Flour

Both wheat flour and cornflour act as thickening agents. Cornflour will give better results, but ordinary flour will also work. You may just need to use a little more. 

If you merely add dry flour or cornflour to your mash, it will turn into a glue-like, lumpy mess. The trick is to make a smooth paste with a thick, liquid consistency.

Place a tablespoon of cornflour, or 2 tablespoons of regular flour, in a cup and add a little slightly warm milk. Mix it well until there are absolutely no lumps, and add gradually to the mash, stirring it in very well. It should thicken up beautifully.

If the mash is still too soft, repeat the process until it is thick enough.

See Related Article: How to Thicken Clam Chowder – A Guide

How To Thicken Mashed Potatoes With Other Ingredients

how to thicken mashed potatoes

It is possible to thicken mashed potatoes by adding a little dried milk powder and stirring it in carefully. Adding some grated cheese also works well, and adds a delicious flavor to the mash.

The best trick of all is to add a little instant dried potato powder and stir well. This will bulk up the mash and thicken it perfectly.

How To Thicken Mashed Potatoes By Removing Surplus Moisture

Heat causes evaporation, so if you heat the runny mash, some of the excess water will evaporate, and the mash will thicken. If you heat the mash in a pot on the stove, you run the risk of the bottom burning.

Preheat the oven to 325° Fahrenheit. Place the runny mash in an uncovered ovenproof dish and put it in the oven. Check and stir it every 10 minutes, until it has thickened.

The same thing can be done by putting the mash in the microwave in an uncovered dish and heating it, opening the microwave and stirring every 2-3 minutes until moisture has escaped.

By following the above tips for how to thicken mashed potatoes, you will never again have to throw out that runny mash.

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Peter's path through the culinary world has taken a number of unexpected turns. After starting out as a waiter at the age of 16, he was inspired to go to culinary school and learn the tricks of the trade. As he delved deeper, however, his career took a sudden turn when a family friend needed someone to help manage his business. Peter now scratches his culinary itch on the internet by blogging, sharing recipes, and socializing with food enthusiasts worldwide.

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