Preheat the oven to 350°F, and line a loaf pan with tinfoil.
In a medium bowl, mix together the meatloaf ingredients, except the hamburger buns. Place the mixture into the lined loaf pan.
Bake the meatloaf for 1 hour. Let the meatloaf cool completely, cut into 10 slices.
Preheat the George Foreman grill.
Place the meatloaf slices on the preheated grill. Place the lid on the grill.
Grill the meatloaf slices for 6-7 minutes per side.
Meanwhile, in a small bowl, mix together the topping ingredients.
Top one bun with a meatloaf slice, 2 Tbsp. topping mixture. Serve with a side of mashed potatoes for a true comfort meal.
For the Evolve Grill preheat to 400° and cook for 2-3 minutes
For the Indoor/Outdoor grill, preheat to setting 3 and cook for 4 minutes per side