Nutrition per serving may change if servings are adjusted.
⅓ cup fat-free milk
2 egg whites
1 cup soft whole-grain bread crumbs (1⅓ slices bread)
¼ cup chopped green onions
2 teaspoons dried Italian seasoning, crushed
¼ teaspoon salt
⅛ teaspoon ground black pepper, plus more for garnish
1 pound lean ground beef
Nonstick cooking spray
1 tablespoon butter
1½ cups sliced fresh mushrooms
1 clove garlic, minced
¼ cup thinly sliced green onions, plus more for garnish
1 (8 ounce) container light sour cream
2 tablespoons all-purpose flour
¾ cup cold water
2 teaspoons instant beef bouillon granules
Preheat oven to 350°F. Line a 2-quart rectangular baking dish with foil; set aside.
In a large bowl combine milk and egg whites; beat with a fork until well mixed. Stir in bread crumbs, ¼ cup chopped green onions, the Italian seasoning, salt, and the ⅛ teaspoon pepper. Add ground beef; mix well. Shape beef mixture into a 7x4-inch rectangle in the prepared baking dish.
Bake about 1 hour or until internal temperature reaches 160°F (see Tips). Spoon off fat. Let meat loaf stand for 10 minutes. Using two spatulas, carefully transfer meat loaf to serving platter, draining off as much fat as possible.
Meanwhile, for sauce, coat a medium skillet with cooking spray. Add butter; melt over medium heat. Add mushrooms and garlic; cook about 4 minutes or until mushrooms are nearly tender. Stir in ¼ cup sliced green onions; cook for 1 minute more. In a small bowl stir together sour cream and flour. Stir the cold water and beef bouillon granules into the mushroom mixture. Stir sour cream mixture into mushroom mixture in skillet. Cook and stir until thickened and bubbly. Cook and stir for 1 minute more. Add additional water if needed to thin to desired consistency. Serve sauce over meat loaf. If desired, sprinkle with additional sliced green onions and pepper.
Tips: The internal color of a meat loaf is not a reliable doneness indicator. A beef loaf cooked to 160°F is safe, regardless of color. To measure the doneness of a meat loaf, insert an instant-read thermometer into the center of the loaf.