Preheat the oven to 375 degrees F and line a rimmed baking sheet with parchment paper.
In a large bowl, combine the ground beef, ground pork, breadcrumbs, egg, onion, garlic, Worcestershire sauce, thyme, salt, and pepper. Mix with clean hands until the ingredients are evenly distributed.
Shape the mixture into a loaf about 9 inches long and place it in the center of the baking sheet.
Lay the bacon slices over the top and sides of the loaf, tucking the ends underneath so the bacon stays in place.
In the same bowl, toss the carrots, parsnips, and potatoes with the olive oil, rosemary, and a pinch of salt and pepper until the vegetables are coated.
Spread the vegetables around the meatloaf on the baking sheet in a single layer.
Bake for 55 to 65 minutes until the meatloaf reaches 160 degrees F internally and the bacon is browned. Let the loaf rest for 5 minutes before slicing.