Filet Mignon with Red Wine Sauce

Ingredients (10)

• 1 medium onion, thinly sliced
• 3 tablespoons butter, divided
• 2 garlic cloves, minced
• 3/4 teaspoon salt, divided
• 1/2 teaspoon dried oregano
• 2 tablespoons tomato paste
• 1-1/4 cups dry red wine or beef broth
• 1/2 teaspoon pepper, divided
• 6 beef tenderloin steaks (4 to 6 ounces each)
• 3 tablespoons olive oil