Preheat the oven to 400 degrees Fahrenheit.

Place the pretzels in a heavy-duty freezer bag and crush them into coarse crumbs using a rolling pin.

Set up three shallow bowls: one with seasoned flour, one with beaten eggs and milk, and one with the crushed pretzels.

Dip each piece of chicken into the flour, shaking off the excess, then into the egg wash, and finally press it firmly into the pretzel crumbs.

Place the chicken on a wire rack over a baking sheet.

In a small saucepan over medium heat, melt the butter and whisk in the flour to form a roux.

Slowly pour in the milk, whisking constantly until the mixture thickens and begins to bubble gently.

Lower the heat and stir in the Dijon mustard and grated cheddar cheese until the cheese melts into a silky, golden ribbon.

Bake the chicken for 15 to 20 minutes, depending on the thickness of the cutlets.

While the chicken bakes, prepare the sauce as described above.

Once the chicken is golden brown and reaches an internal temperature of 165 degrees, remove it from the oven and let it rest for a few minutes.

Drizzle the warm sauce generously over the crispy chicken and serve.