Mushroom Medallione Pasta with Porcini Sauce

Mushroom Stuffing: 

2 tablespoons extra-virgin olive oil

2 cloves garlic, minced

2 cups button mushrooms, halved

1 yellow onion, diced

Sea salt

Freshly cracked pepper

1/4 cup dry white wine

1 tablespoon porcini powder

1 cup ricotta cheese

1/2 cup fresh parsley, finely minced

1/4 cup Romano cheese, grated

1 egg

8 sheets pasta, cut into 2-inch squares

Demi-Glace, for serving, recipe follows

Romano cheese, shaved, for garnish

Coarsely cracked pepper, for garnish

Demi-Glace:

10 pounds split veal bones

2 tablespoons olive oil

1 cup fresh parsley

1 tablespoon whole black peppercorns

3 carrots, roughly chopped

2 bay leaves

2 onions, quartered, peels still on

2 sprigs thyme

1 rib celery, roughly chopped

1 leek, roughly chopped

6 ounces tomato paste

2 sage leaves