Preheat the oven to 375 degrees. In a large bowl, combine the ground beef, ground pork, mushrooms, thyme, onion, garlic, breadcrumbs, egg, salt, and pepper. Mix until just combined.
Shape the mixture into a loaf and place it in a loaf pan. Bake for 50 to 55 minutes until the internal temperature reaches 160 degrees.
While the meatloaf bakes, heat the olive oil in a saucepan over medium heat. Add the wild rice and stir for one minute to toast it lightly.
Pour in the beef broth, bring to a boil, then reduce to a simmer. Cover and cook for 45 minutes until the rice is tender and the liquid is absorbed.
Let the meatloaf rest for 10 minutes before slicing. Fluff the wild rice with a fork and serve it alongside the meatloaf slices.