This suggestion is really a compromise between accuracy and viable copy. A "plato de producto" really means a dish based on fine ingredients, in which the ingredients themselves are the dominant element: not over-elaborated, well prepared, allowing the beef, foie and ceps (in this case) to be appreciated. The concept is well explained here:

"Es un plato famoso de la gastronomía gallega y es de los que llaman "plato de producto" porque lo que cuenta es el producto básico del plato, el pescado, su frescura y su sabor y una guarnición que no enmascare la materia prima."
http://www.spanishpodcast.org/fotos/santiago/comidas/sw/P100...

So it means, if you like, a dish based on and showcasing quality ingredients. But I just can't come up with a phrase that captures this precisely without being unacceptably clumsy. I think "a quality dish" would tend to imply the same thing. It's often said that the key to a quality dish is quality ingredients, with the implication that the quality of the ingredients shines through. So I think the point would come across like this.

or Haute Cuisine but I'd go with Gourmet platter