Heat a cast iron skillet to medium with 1 TBSP of olive oil. Chop 2 TSBP of red onion and 2 of those baby yellow bell peppers. Add salt and pepper. Sauté until tender.
On a cast iron griddle or pan on another burner, toast a sandwich bun. I toasted it dry without butter or oil.
Meanwhile, cut one boneless chicken breast tenderloin into small pieces of about 1/2 inch square, salt and pepper. Add to the skillet and cook until done, (3 – 4 minutes), Add 1/2 cup chopped spinach or baby spinach, add a TBSP of mustard vinaigrette and put a lid on for two minutes to cook.
While the veggies and chicken are finishing, cut two slices of tomato and grate a bit of parmesan cheese, just enough to sprinkle over the sandwich.
To assemble, spread some mayo on the top side of the bun and place two thin slices of tomato. On the bottom side of the bun, spread your cooked veggies and chicken and sprinkle grated parmesan over it.
Add salt and pepper.
This was delicious, the blend of textures, the crispy coated bread, the gooey parm, the slight crunch of the peppers, with the tender spinach and the freshness of the tomatoes. The flavors are full of freshness and umami. I used only a small bit of parm, but it was just enough to be creamy. The mustard vinaigrette finished it off perfectly with a bit of tang and bite.