Egg And Spinach Stuffed Meat Loaf

Name: Egg-And-Spinach-Stuffed Meat Loaf
Ingredients: 3 slices crustless white bread; Kosher salt, to taste; 16 oz. spinach leaves, stemmed; 12 oz. ground beef chuck; 12 oz. ground pork; 4 oz. thinly sliced mortadella, minced; 1 cup finely grated Pecorino Romano or Parmesan; 1 tsp. minced fresh rosemary leaves; ¼ tsp. freshly grated nutmeg; 2 eggs, lightly beaten, plus 3 hard-boiled eggs; 2 cloves garlic, minced; 1 medium onion, minced; Freshly ground black pepper, to taste; 2 tbsp. extra-virgin olive oil; ½ cup beef broth; ½ cup white wine