In a skillet over medium heat, add a splash of oil and the finely diced yellow onion. Sauté for about 5–7 minutes until the onion is soft and translucent, releasing its natural sweetness. Once cooked, set the onion aside to cool while you prepare the other ingredients for the best smoked meatloaf.

In a mixing bowl, combine the breadcrumbs and milk, stirring to form a paste. Allow the mixture to sit for 5 minutes; this step helps the breadcrumbs absorb the milk and creates a better texture in the meatloaf. Meanwhile, gather the rest of your ingredients for the best smoked meatloaf.

In a large bowl, combine the ground beef, cooled sautéed onion, minced garlic, eggs, and the breadcrumb paste. Use your hands or a spatula to mix until everything is just combined—be careful not to overmix, as this can make the meatloaf dense. The mixture should be cohesive and aromatic, setting the stage for the best smoked meatloaf.

Transfer the mixture onto a parchment-lined tray and shape it into a loaf that measures about 9 inches long and 5 inches wide. Create a slight indentation down the center to help avoid a dome shape while it smokes. This is crucial for even cooking and to achieve that perfect meatloaf profile.

In a small saucepan over medium heat, combine ketchup, molasses, honey, brown sugar, apple cider vinegar, Worcestershire sauce, and a dash of hot sauce. Stir frequently and simmer until the mixture is smooth and well-blended, about 5 minutes. This glaze will add a sweet and tangy finish to your best smoked meatloaf.

Set your smoker to preheat at 250°F (120°C). Once it reaches this temperature, carefully place the shaped meatloaf inside, ensuring there’s space around it for smoke circulation. Allow the meatloaf to smoke for 1 hour before applying any glaze, letting those smoky flavors deeply infuse.

After 1 hour, open the smoker and baste the meatloaf generously with the sweet and tangy glaze using a brush. Close the smoker and continue cooking for an additional 1.5 to 2 hours. Baste the meatloaf every 30 minutes to build layers of flavor and a beautiful caramelized exterior, enhancing the overall taste of your best smoked meatloaf.

Use a meat thermometer to check the internal temperature of the meatloaf, ensuring it reaches 160°F (70°C). This ensures it is cooked through while remaining juicy. Once the perfect temperature is achieved, remove the meatloaf from the smoker and let it rest for 5–10 minutes before slicing, allowing all those delectable juices to settle.