This is DIVINE.
6 large fresh field/portobello mushrooms
3 tbsps butter
2,3,4 (according to taste) cloves garlic crushed
1/2 cup fresh flat leaf parsley chopped or 1tbsp dried parsley
1 French baguette
Mix/mash the garlic and parsley with the butter.
Place mushrooms on an oven tray, stalks up, and divide garlic butter between them
Bake in a hottish (180c) oven for about 15 mins so the butter melts and the mushroom juices start to flow
Cut baguette lengthways and pour mushroom juices onto one side
Spread Dijon mustard on one side
Add mushrooms, a little salt and pepper and squish the bread together again.
This beats a steak sandwich any day and keeps the veggie brigade happy too.