Make the tomato sauce first. Melt the butter and add the garlic, oregano and tomato puree. Cook out for a few minutes then add the tinned tomatoes. Season with salt and pepper then cook for 20-30 minutes until reduced.
Bash the chicken to tenderise then slice up into even pieces. Coat in flour, then egg, then breadcrumbs. Heat the oil and shallow fry until golden, cooked through and crispy.
Toast the baguette pieces then top with some of the tomato sauce, followed by the chicken, more tomato sauce then lots of cheese. Bake for 10 minutes or until the cheese has melted.