Slice the chicken breasts horizontally into 1/4–1/2 inch thick slices. Use a sharp knife and be careful!
Season each slice lightly with a pinch of salt.
Spread about 1 teaspoon of mustard on each piece.
Roll each slice tightly into a small roll.
Arrange rolls in a lightly oiled baking dish, leaving small gaps between them.
Sprinkle rolls with paprika, black pepper, and 1/2 tablespoon of panko breadcrumbs.
Add a pinch of salt over the top and spray lightly with olive oil.
Bake at 425° for 25–30 minutes until golden and cooked through.
Enjoy warm or save leftovers, they reheat well!