Start by preparing your chicken. Pound it as thin as possible so it cooks quickly and stays juicy.
Place one chicken breast at a time between two pieces of plastic wrap. Pound it with a meat mallet or rolling pin until it is as flat and uniform in thickness as possible.
Season the chicken on both sides with salt, pepper, and garlic powder to taste, then set aside.
To make the sauce
Start by melting the butter in the bottom of a medium to large pot over medium heat.
Once the butter has melted, add the flour. Stir to combine and cook the flour slightly.
Now add the milk and bring it just to a boil. Watch the pot to prevent it from boiling over. Stir until it has thickened, about a minute.
Remove from the heat and stir in all the cheese until melted. Set aside.
To cook the asparagus
Cut off the bottom 2 inches or so of the asparagus spears, as they are too tough. You can save them to make stock.
Cut the spears into bite-sized pieces.
Add the asparagus to a cast iron pan, then add just enough water to cover the bottom of the pan.
Bring to a simmer to begin cooking the asparagus.
Once the water has evaporated, add oil and continue to cook the asparagus until it’s soft. Set aside
To cook the chicken
Heat up a cast iron pan over medium high heat. Drizzle some cooking oil in the bottom and add the chicken. Work in batches if you can't fit it all.
Once the chicken has browned on one side, flip it over and cook the other side. The chicken should flip easily when it’s browned enough.
Cook the chicken until it reaches an internal temperature of 165°F in the thickest part of the meat.
Remove the chicken from the pan and place it on a cutting board. Let it rest for 5 minutes, then cut into bite-sized strips.
To put the dish together
Heat your cast iron pan until it's hot again, then add the cheese sauce. Stir to reheat quickly, then add the chicken and asparagus. Remove from the heat and serve.
Notes
If you can't find the Tillamook 4 Cheese Italian Blend, then just use a combination of sharp cheddar, provolone, mozzarella, and parmesan.