How to Fix Runny Mac and Cheese

Published Categorized as Cooking Tips
Runny mac and cheesefahrwasser /Depositphotos

Wondering how to rescue a runny mac and cheese sauce? Find out how to thicken it up in a pinch with this easy-to-read guide.

Macaroni and cheese is a staple of Southern cuisine. It is the pinnacle of comfort food: darn tasty, easy to prepare, and requiring simple ingredients found in every pantry. Plus, it’s one of those dishes that everyone loves to eat, from picky kids to capricious eaters.

The great thing about mac and cheese is that there are countless ways to prepare it: on the stove, in the oven, even under the lid of the grill. Some add peas, others chicken, and still others add tuna. It can be as uncomplicated as a box of Kraft or as sophisticated as a restaurant-worthy masterpiece.

Though this dish lends itself to experimentation, you should make sure to carefully measure your ingredients and follow the directions so that you end up with a creamy, cheesy sauce. Failing to measure properly can result in a sauce that’s too runny.

If you find yourself with a runny sauce for your mac and cheese, don’t fret: you can still save it. Sometimes you can look back at the ingredients and see if you added too much or too little of something and adjust accordingly. That said, what if your sauce is still runny?

To fix runny mac and cheese, add a thickening agent, like flour or cornstarch; simmer the sauce to reduce the liquid; mix in an egg yolk, or simply add more cheese.

The key to fixing runny mac and cheese is to make sure the sauce hasn’t been added to your noodles yet. In case you have already mixed it with the noodles, run it through a sieve to separate it.

The sauce should be on the stove, in a saucepan or a large pot, so that you can stir in ingredients smoothly and incorporate them properly, without the noodles getting in the way or overcooking to mush.

Fixing a Runny Cheese Sauce

Here are four simple ways to transform your runny sauce into a creamy delight:

Add Flour or Cornstarch

Cheese sauces all begin with a béchamel sauce, which is simply combining melted butter and flour to create a roux, letting it cook, and then adding milk to the mixture. An easy way to thicken your cheese sauce is to add more flour or cornstarch to your béchamel base.

To thicken your béchamel sauce, create a slurry by combining a couple of teaspoons of flour or cornstarch with cold water. Stir this mixture into your cheese sauce on the stove, letting it come almost to a boil so it can thicken. If your sauce is still runny, you can slowly add more slurry until it reaches your desired consistency.

Simmer to Thicken

One of the simplest ways to thicken a runny sauce is by simmering the sauce as-is on the stove. Set the heat to medium-low and keep stirring. As the sauce is heated, excess moisture will evaporate. Sooner or later, it will reach the exact consistency you’re looking for.

Make sure to keep stirring to keep the sauce from sticking to the bottom of your pot and burning. Keep the temperature moderate, just below a boil. Diary has the tendency to curdle at high heat, so going easy on the heat keeps the milk and cheese from separating from the sauce.

Mix In an Egg Yolk

Another quick and easy way to repair your runny cheese sauce is to mix in an egg yolk. To do this, carefully separate the yolk from the egg whites in a bowl. Beat the yolk with a fork, then slowly add the cheese sauce to the bowl with the egg yolk.

After you have combined the egg yolk with the cheese sauce, return the mixture to the saucepan on the stove. Turn up the heat to simmer the sauce, stirring frequently, until it has reached your desired consistency.

To keep from thickening the sauce too much, you can add small amounts of egg yolk at a time. This lets you have full control over how much the egg yolk thickens the sauce.

Add More Cheese

Is there such a thing as too much cheese? Not when it comes to macaroni and cheese! Adding more cheese to your runny sauce will not only help it thicken up, but it will also add flavor and make the sauce creamier. The creamier the better with mac and cheese, so give this solution a try!

To use this method, just slowly add more cheese to the sauce. Both grated and cubed cheese work well for this. Make sure to keep stirring the sauce as you add in the cheese so that it’s able to combine with the sauce. Simmer the cheese and sauce until thickened.

What If the Sauce Gets Too Thick?

So, you’ve solved the issue of your sauce being too runny, but it’s too thick now. What can you do to fix this problem?

Fixing sauce that’s too thick is incredibly simple. By adding milk or cream a tablespoon at a time, you can easily thin out your cheese sauce. Adding a bit at a time makes it so you don’t end up with a sauce that’s too runny!

Should I Stir My Cheese Sauce?

One way to keep your cheese sauce from becoming too runny or too thick is to stir it regularly. Stirring often allows you to check in on the thickness of your sauce. This makes it easier to make small adjustments to keep your sauce at your desired consistency.

Stirring also helps to keep the sauce from burning. Keeping your sauce just below a boil helps it to thicken without causing the cheese to separate from the sauce. Stirring is an easy way to make sure your sauce stays at the right temperature, resulting in out-of-this-world mac and cheese.

Final Thoughts

A creamy, smooth cheese sauce is key to creating the perfect mac and cheese. If your sauce is too runny, add a thickening agent like cornstarch or flour for an easy way to solve the problem. If it’s suddenly too thick, a splash of milk should do the trick.

Mac and cheese is a simple, tasteful dish that can be dressed up to please any crowd. There are so many additions that perfectly complement the cheesy flavor of this pasta dish, like breadcrumbs, veg, and tuna.

Whether you’re making a weeknight dinner for your hungry family or preparing a dish for a potluck, mac and cheese is the perfect choice.

By Jim Stonos

When Jim isn't in the kitchen, he is usually spending time with family and friends, and working with the HCW editorial team to answer the questions he used to ask himself back when he was learning the ropes of cooking.