Preheat oven to 375 degrees F
In a medium skillet, sauce the onions in the 2 tbsp of ghee (or other cooking fat) until soft, add garlic and mushrooms, sprinkle with a small amount of sea salt and continue to cook, stirring, for about 3 minutes, then remove from the heat.
In a large bowl, combine the beef, eggs, almond flour, 3 tbsp ketchup, mustard, Italian seasoning, black better and cooked onions/garlic/mushrooms. Mix with your hands until well incorporated but try not to over-mix, since this will toughen the meat.
Transfer the meat mixture to a 9x5 loaf pan and bake in preheated oven for 20 minutes. After 20 minutes, remove and spread ¼-⅓ cup of the ketchup over the top of the loaf, return to oven and continue to bake for 40-45 minutes more until the center is cooked (internal temp of 160 degrees F).
Allow the loaf to rest for 10 minutes, then slice and serve. Enjoy!