Fold the pastry sheets in half and place the halves on top of each other, cut the pastry to fit on top of an oven proof frying pan. Set the pastry aside under a damp kitchen towel.
Heat the olive oil in the frying pan, add the mushrooms and garlic and sauté for 2 minutes, add the whole grain mustard and rosemary.
Heat the oven to 200°C, Remove the pastry from the kitchen towel one piece at a time, brush with olive oil and spread a little mustard and then sprinkle with bread crumbs. Do this with each pastry layer. Once all four layers are stacked Place it in the pan over the mushrooms, tuck in the edges.
Place into the oven and bake until the pastry is golden and then turn out.
Cooks tip: Use a layer of puff pastry instead of the phylo pastry as a different option.
Cooks tip: Try using other grains such as Pearl barley, buckwheat or quinoa. Or a mixture of grains make a lovely salad.