Shepherd’s Pie Casserole

Ingredients:

• 1 pound ground beef
• 3/4 cup onion
• 2 garlic cloves, minced
• 3 tablespoons canola oil, divided
• 1 cup chopped fresh mushrooms
• 1 tablespoon tomato paste
• 1/2 cup beef broth
• 2 teaspoons prepared horseradish
• 1 teaspoon ground mustard
• 1 1/2 teaspoons salt, divided
• 1/4 teaspoon pepper
• 1/2 cup diced green pepper
• 1/2 cup diced sweet red pepper
• 8 medium potatoes, peeled and cubed
• 1/3 cup hot milk
• 1 cup (4 ounces) shredded cheddar cheese
• 2 egg whites

Directions:

1. In a large skillet, brown beef, onion and garlic in 2 tablespoons of oil.
2. Add the mushrooms.
3. Cook and stir for 3 minutes; drain.
4. Place the tomato paste in a bowl.
5. Gradually whisk in broth until smooth.
6. Stir in horseradish, mustard, 1 teaspoon salt and pepper.
7. Add to meat mixture.
8. Pour into a greased 11-inch by 7-inch baking pan; set aside.
9. In the same skillet, sauté the peppers in remaining oil until tender, about 3 minutes.
10. Drain and spoon over meat mixture.
11. Cook potatoes in boiling salted water until tender; drain. Mash with milk, cheese and remaining salt.
12. Beat egg whites until stiff peaks form; gently fold into potatoes.
13. Spoon over pepper layer.
14. Bake, uncovered, at 425° for 15 minutes.
15. Reduce heat to 350°; bake 20 minutes longer or until meat layer is bubbly.