Step 1: In a large pot, bring water to a boil. Add the cubed potatoes and cook until tender, about 15-20 minutes.
Step 2: Drain the potatoes and return them to the pot. Add milk, butter, salt, and pepper. Mash until smooth and creamy.
Step 3: Stir in the cheddar cheese, crumbled bacon, and chopped green onions. Set aside.
Step 4: Preheat your oven to 350°F (175°C) and lightly grease a loaf pan.
Step 5: In a large mixing bowl, combine the ground beef, breadcrumbs, chopped onion, minced garlic, egg, Worcestershire sauce, salt, pepper, and oregano. Mix until just combined; do not overmix.
Step 6: Press half of the meat mixture evenly into the bottom of the prepared loaf pan. Top this layer with the prepared loaded mashed potatoes, spreading them smoothly. Finally, carefully add the remaining meat mixture on top, pressing down gently to fully seal the potato layer inside.
Step 7: Bake in the preheated oven for 1 hour, or until the meatloaf is cooked through and reaches an internal temperature of 160°F (70°C).
Step 8: Once baked, allow the meatloaf to rest for 10 minutes before slicing.
Step 9: Slice the meatloaf and serve warm, garnished with additional green onions or chives if desired. Enjoy with your favorite sides!