It's my birthday month! 
That means that calories don't count.
In my world they kind of never do, but ESPECIALLY not in the month of March, ever. You know, starting a new year right and all that. Har dee har har.
This mac, though, should be a part of your life IMMEDIATELY. It's vegetarian (up to you, you can throw in a chicken bouillon cube or not depending on who you're making this for) but has tons of flavor from the walnuts and onions so you don't miss bits of bacon or whatever, and features more rosemary from my sister's yard, so it's basically organic, which makes it healthy.
You need this, birthday or not. Promise.
You'll need pasta, like any good mac - any short cut you like. Then you'll need butter, 2 onions, garlic, dijon mustard, flour, milk, shape white cheddar cheese, a chicken bouillon cube (optional, this technically makes the dish not vegetarian), walnuts, fresh rosemary, and panko bread crumbs. YUM. 
Now, caramelizing the onions is what takes the longest in this recipe, but you can do that a day or so in advance. I worked on the onions while I cooked the pasta and made the cheese sauce to keep things moving all at once. SO. Peel and thinly slice the onions. 
Throw them in a pan, turn the pan to medium, sprinkle with salt, drizzle of olive oil. Stir every few minutes while you do other stuff. 
The onions will cook low and slow for 30 minutes or even more if you have time. 
We're looking for super soft, slightly golden, and mushy and sweet. SO good. 
While the onions are working, cook the pasta to 2 minutes BEFORE al dente, then drain it. Prep the other ingredients, too! Grate cheese, chop rosemary, toast walnuts, mince garlic. 
For the cheese sauce, melt butter in the bottom of a large pot (since the onions take so long I use the same pot I boiled the pasta in) and add the garlic, rosemary, mustard, and bouillon cube if you're using it.
Let the butter foam and the garlic become fragrant, and HOLY SHIT THE SMELL. This is when you'll start to be so happy you are making this recipe. 
Sprinkle the flour over the garlic mixture, and stir it together to make a paste. Then, pour the milk in really slowly, whisking or stirring as you go. 
When the milk mixture bubbles and thickens, add the cheese and stir it in to melt. Taste the sauce and add salt - it should be pretty salty since we'll be adding all the pasta to it. 
When the sauce is thick and melty and tasty, add the pasta, the onions, and the walnuts. 
Spread it into a dish, top with panko and more walnuts. 
Bake! 30 minutes at 375F or longer if you make this in advance and it's coming out of the fridge. Just until the topping is browned and the cheese sauce is bubbly. 
Holy hell, guys. This is a really wonderful flavor combination - the rosemary and walnuts are so earthy and the sharp cheddar adds a nice tang to everything. 
I'm a massive fan of fancy mac and cheeses, as you know. This juuuuuust might be our new fav, though. Enjoy!
Rosemary Walnut Mac w/ Caramelized Onions
Ingredients
- 2 onions thinly sliced
- salt and olive oil
- 16 ounces short-cut pasta cooked to 2 minutes shy of al dente and drained
- 4 tablespoons butter
- 3 cloves minced garlic
- 1 chicken bouillon cube skip if vegetarian and just add extra salt
- 1 sprig fresh rosemary leaves stripped and chopped
- 2 tablespoons dijon mustard
- 3 tablespoons flour
- 3 cups milk
- 3 cups freshly grated sharp white cheddar cheese
- ½ cup toasted chopped walnuts
- ¼ cup panko bread crumbs
Instructions
- In a large skillet, add a drizzle of olive oil, the onions, and a sprinkle of salt. Turn heat to medium-low and cook slowly for 30 minutes to 1 hour until very soft and golden, stirring every few minutes.
- Meanwhile, make the rest of the mac. In a pot (I use the pot from boiling the pasta), add the butter, garlic, rosemary, bouillon, if using, and dijon over medium-high heat. Stir to melt and create a paste. Sprinkle the flour over the mixture and stir for one minute. Pour the milk into the flour mixture slowly, stirring or whisking as you pour. When all the milk is added and the mixture has bubbled, stir in all the cheese to melt. Taste the cheese sauce and add salt to your preference.
- When the cheese sauce and the onions are done, add the cooked pasta, onions, and most of the walnuts to the sauce. Stir together and taste one more time for seasoning. Pour the mac into a baking dish and top with the rest of the walnuts and the panko bread crumbs.
- Bake at 375F for 20-30 minutes until the cheese sauce is bubbly and the top is lightly browned. Eat. Enjoy!
Notes
- You can make this up to 4 days in advance and store in the fridge, just bake a little bit longer to heat all the way through!
trying this, sounds scrumptious!