Step 1: Preheat your oven to 350°F (175°C). Lightly grease a loaf pan or line a baking sheet with parchment paper if free-forming the loaf.
Step 2: In a small skillet, heat 1 tablespoon of olive oil over medium heat. Add the finely chopped onion and cook until softened and translucent, about 5-7 minutes. Add the minced garlic and cook for another minute until fragrant. Remove from heat and let cool slightly.
Step 3: In a large mixing bowl, combine the breadcrumbs and milk (or beef broth). Let sit for 5 minutes to allow the breadcrumbs to soak up the liquid.
Step 4: Add the cooled onion and garlic mixture to the breadcrumb mixture. Then add the ground beef, ground pork, large egg, ketchup, Worcestershire sauce, Dijon mustard, dried thyme, salt, and black pepper.
Step 5: Using clean hands, gently mix all the ingredients until just combined. Be careful not to overmix, as this can lead to a dense, tough meatloaf.
Step 6: Transfer the meat mixture to the prepared loaf pan and gently press it down evenly, or form it into an oblong loaf on the parchment-lined baking sheet.
Step 7: In a small bowl, whisk together the ingredients for the glaze: ketchup, brown sugar, and apple cider vinegar. Spread about half of this glaze evenly over the top of the meatloaf.
Step 8: Bake for 45 minutes. Remove from the oven, spread the remaining glaze over the top, and return to the oven for another 15-25 minutes, or until the internal temperature reaches 160°F (71°C) on a meat thermometer.
Step 9: Once cooked, remove the meatloaf from the oven and let it rest in the pan for 10-15 minutes before slicing. This resting period is crucial for the juices to redistribute, ensuring a moist and flavorful slice.
Step 10: Slice and serve hot. Enjoy your perfectly crafted homestyle meatloaf!