To make this mac n cheese, start by preparing the pasta according to package instructions. Once it's done, drain it well and set it aside.
Next, heat a large skillet, on the stove, over medium heat.
Once the pan is hot, add in the butter.
Dice the shallot and mash the garlic, then add it to the pan with the melted butter and cook for 1-2 minutes. Then, add in the diced chilis and continue stirring.
Stir to incorporate the chilis into the butter. Then, add in the paprika and flour and stir again to coat well. The mixture will be thick, and that is okay!
Next, carefully pour in the milk, heavy cream, and dijon mustard, stirring until everything fully combines. Allow it to cook for 3-4 minutes, stirring regularly. Add in a pinch of the kosher salt and ground black pepper.
Then, remove the pan from the heat and add in 3 cups of the cheddar cheese and the freshly-grated parmesan cheese. Gently mix until smooth.
Next, spray a half baking sheet (18 x 13) with non-stick spray.
Then, add the pasta to the tray, spreading it out in an even layer.
Evenly sprinkle 1 cup of the panko breadcrumbs over the pasta. Then, pour the cheese sauce mixture over the top.
Gently toss to coat the pasta well in the sauce and breadcrumbs.
Then, add the remaining panko breadcrumbs on top of the pasta, followed by the remaining shredded cheddar cheese.
Finally, transfer the tray to the oven, approximately 6-7 inches underneath the broiler.
Broil the mac n' cheese for 5-6 minutes, until it is evenly browned and the panko breadcrumbs on top have crisped. You might need to rotate the tray under the broiler, as needed.
Once it's done, remove it from the oven and allow it to cool slightly. Then, serve and enjoy!