Tournedos Of Beef With Caramelized Onion Potato Gratin Recipe

• 4 slc country-style bread
•     Extra virgin olive oil as needed
•     Salt to taste
•     Freshly-grnd black pepper to taste
• 2 Tbsp. extra virgin olive oil
• 1 Tbsp. unsalted butter
• 4 x beef fillet steaks - (abt 6 ounce ea)
•     Salt to taste
•     Coarsely-grnd black pepper to taste
• 1 lb shiitake mushrooms cleaned, quartered
• 2 x shallots finely diced
• 1 c. red wine
• 1 c. beef broth
• 2 Tbsp. Dijon mustard
• 2 Tbsp. cool unsalted butter
• 2 Tbsp. extra virgin olive oil
• 3 lrg Spanish onion peeled, and
•     sliced thinly
• 2 x garlic cloves finely minced
•     Salt to taste
•     Freshly-grnd black pepper to taste
• 4 lrg potatoes peeled, and
•     sliced thinly
• 3 Tbsp. balsamic vinegar
• 1 1/4 c. heavy cream
• 1/4 c. finely-minced fresh parsley
• 1 c. grated Gruyere cheese

Directions