In this post, I’ll teach you how to make a mornay sauce, which is more commonly just called cheese sauce. There are many ways you can alter this approach to make it truly your own, but this is just a basic blueprint of how you can legitimately craft your own “Kraft” mac and cheese (okay, that was corny, but anyway…).
Pictured below are some of the cheeses you can use to make the sauce. Fontina is a cheese I always try to incorporate into my cheese sauces (as it has a smooth consistency, and is more stable under heat), and the gouda and gruyere just seemed like they’d be good flavor and texture fits. Generally speaking, any cheese you can grate tends to work just fine. That being said, while Parmesan and similar cheeses are a good cheese to tighten or stabilize a sauce, I don’t recommend making a cheese sauce out of only parm’ (unless you’re making alfredo sauce!).

First, here’s how to make the roux
These are the ingredients you’ll need:
- Butter
- Flour
Here are the Steps:
Melt butter in a small pot over medium/low-medium heat.
Whisk in flour until you reach the consistency of damp sand. Add as much flour as you like until it’s the appropriate consistency. The textbook ratio is 2:1 (by volume), flour to fat.

Here’s what the roux looks like when finished.

Meanwhile, gently bring a bit of milk to a simmer in a saucepan. Remember whenever heating milk, to stir frequently, as milk is susceptible to scorching on the bottom.
Whisk a bit of your roux into the simmering milk. Allow the milk to return to a simmer after you add each bit of roux, as the thickening properties of roux are enacted by heat.
It’s hard to see because you really can’t stop stirring. You want this early version of the sauce to be viscous, but not too thick (paint is the consistency that comes to me).
In my professional opinion, practice on this before doing it for company or showing off at a dinner party because it takes a while to get used to making this.
If you ever feel your sauce is getting too thick, milk is your thinning agent. No harm will come to your sauce by adding more milk, so long as it’s stirred in evenly.
The sauce should be smooth on the tongue.
We had some ground up turmeric and wanted to try to incorporate it. We added a half tablespoon of turmeric to the cheese sauce. It actually colored the sauce a bit more giving it a warmer color
While I originally planned to use the sauce to just make macaroni and cheese, I noticed a container of fresh spinach tortellini taking up room in the fridge, so it was chosen for the sacrifice.
And as an aside: if this sounds a lot like alfredo sauce, it should, because it is quite similar. The difference between alfredo and mornay is that alfredo sauce is primarily reduced cream, that is then thickened (and seasoned) with grated Parmesan. It contains no flour, so if you’re looking for a gluten-free technique, you can use cream instead of milk.
The key thing to note about this alternate method is that milk doesn’t really reduce, at least not to a thicker product, whereas if cream simmers, it will thicken. I’ve tried to make alfredo with milk as opposed to cream, and no roux (I was trying to appease a friend who was particularly health-conscious. It was also early in my career and was trying to show off), and it really was pretty embarrassing.