Step 1: Preheat your oven to 350°F (175°C). Lightly grease a 9x5 inch loaf pan or line a baking sheet with foil if making a free-form loaf.
Step 2: In a large mixing bowl, combine the ground beef, beaten egg, milk, crushed crackers, chopped onion, green bell pepper, minced garlic, Worcestershire sauce, salt, black pepper, and dried thyme.
Step 3: Using your hands, gently mix all ingredients until just combined. Be careful not to overmix, as this can make the meatloaf tough.
Step 4: Transfer the meat mixture into the prepared loaf pan, pressing gently to form an even loaf. Alternatively, shape it into a rectangular loaf on the foil-lined baking sheet.
Step 5: In a small bowl, whisk together all the glaze ingredients: ketchup, brown sugar, mustard, and apple cider vinegar, until smooth.
Step 6: Spread about half of the prepared glaze evenly over the top of the meatloaf.
Step 7: Bake for 45 minutes.
Step 8: Remove the meatloaf from the oven and spread the remaining glaze over the top. This second layer will create a beautiful, caramelized crust.
Step 9: Return the meatloaf to the oven and continue baking for another 20-30 minutes, or until the internal temperature reaches 160°F (71°C) when measured with a meat thermometer inserted into the center.
Step 10: Once cooked, remove the meatloaf from the oven and let it rest in the pan for 10-15 minutes before slicing. This allows the juices to redistribute, ensuring a moist and flavorful meatloaf.
Step 11: Carefully remove the meatloaf from the pan, slice, and serve hot with your favorite Southern sides.