Ingredients:
2 teaspoons canola oil
1 cup finely chopped white mushrooms
1 cup finely chopped onion
1 carrot, peeled and finely chopped
1 stalk celery, finely chopped
1 pound lean ground beef (7% or less)
1/2 cup quick cooking or old-fashioned oats (not instant)
2 large egg whites (I use 1 whole egg instead)
3 tablespoons ketchup (plus more for brushing on top)
1 tablespoon Worcestershire sauce
1 teaspoon dried thyme leaves (not ground thyme)
1 teaspoon salt
1/4 teaspoon black pepper
1/2 teaspoon garlic powder (or 1 teaspoon minced fresh)
How to make it:
Preheat oven to 350 F degrees. Spray a 4-1/2 x 8-1/2-inch loaf pan with cooking spray.
Heat the oil in a large nonstick skillet set over medium heat. Add the mushrooms, onion, carrot, and celery. Cook, stirring frequently, until the onion is softened, about 5 minutes. Transfer this mixture to a large bowl.
Add the remaining ingredients to the vegetables in the bowl and mix well. Press the meatloaf into the prepared loaf pan.
Bake the meatloaf for 30 minutes. Brush additional ketchup on top of the loaf, if desired. Cook until done, an additional 30 to 45 minutes. (An instant read thermometer inserted into the center of the loaf should read 160 F degrees.)
Remove from the oven and let rest for about 5 minutes. Cut into 8 slices.