Preheat your oven to 375°F and line a small baking dish with parchment paper.
In a large mixing bowl, combine the ground beef, egg, almond flour, finely diced onion, grated carrots, minced garlic, sea salt, black pepper, and dried thyme.
Gently mix the ingredients by hand until just combined, being careful not to overwork the meat to maintain a tender texture.
Shape the mixture into a compact loaf and place it into the prepared baking dish.
In a small ramekin, whisk together the tomato paste, apple cider vinegar, and maple syrup until the glaze is smooth.
Spread the tomato glaze evenly over the top and sides of the meatloaf using a spoon or pastry brush.
Bake for 35 to 40 minutes, or until the internal temperature reaches 160°F.
Remove from the oven and let the meatloaf rest for 5 minutes before slicing to ensure it stays juicy.