Preheat and Prepare: Preheat the oven to 350°F. To simplify cleanup, line a rimmed baking pan with parchment paper before use.
Mix the Ingredients: Combine ground beef, Lipton onion soup mix, breadcrumbs, eggs, milk, Worcestershire sauce, ketchup, chopped onion, and pepper in a large bowl. Use your hands to mix until just combined gently.
Shape the Meatloaf: Shape the mixture into a loaf and place it on the prepared baking pan. Slightly round the edges and flatten the top for even cooking.
Bake the Meatloaf: Bake for 45 minutes. While it bakes, In a bowl, prepare the glaze by thoroughly combining ketchup, vinegar, Worcestershire sauce,garlic powder, brown sugar, black pepper, and onion powder until smooth and well mixed.
Glaze and Finish: At the 45-minute mark, carefully take the meatloaf out of the oven. Using a brush or spoon, generously spread the glaze over the top and sides, ensuring an even coating. Return it to the oven for 15–20 minutes or until the internal temperature reaches 160°F.
Rest and Serve: To ensure maximum flavor and tenderness, let the meatloaf rest for 10 minutes before slicing. This helps the juices settle, ensuring each piece stays moist and flavorful. Serve generously with extra glaze on the side, alongside your favorite comfort food pairings like creamy mashed potatoes or perfectly roasted vegetables.