Veal Pepper Steak with Mushrooms and Cognac Demi

Ingredients

• 6 cups no sodium or low sodium beef stock
• 1 small onion chopped
• 3 cloves chopped garlic
• 1 stalk celery, chopped
• 1 medium carrot, peeled and chopped
• 1 tsp whole black pepper
• 2 sprigs fresh thyme
• Salt, to taste
• Dash of Worcestershire
• 1 tsp potato starch
• 1 tsp cold water
• ½ cup whole black peppercorns
• 2 tbsp chopped fresh herbs (thyme, rosemary, tarragon, oregano, chives, sage, dill, whatever you like)
• 2 tsp kosher salt
• 1 tbsp Dijon mustard
• 2 tbsp butter, melted
• 4 veal tenderloin medallions, cut about 1 ½ to 2 inches thick, about 5-6 oz each
• 7 tsp cold butter, divided
• ½ cup exotic mushrooms (morels, chanterelles, black trumpet, oyster, porcini)
• 1 plump clove garlic, minced
• ¼ cup finely diced shallot
• 1 oz Cognac or Brandy or Armagnac
• ¾ cup demi-glace
• Black pepper to taste
• Salt to taste