Preheat oven to 250°C. Cut the onion and garlic in half, cut the unpeeled ginger into slices. Roast chopped vegetables and spices in a dry frying pan until vibrant and vibrant aromas develop.
Bake the beef bones until they are dark golden brown.
Pour water into the pan. Add bones and sirloins. Place the pan on the fire without bringing to a boil.
Set the temperature at which the broth does not boil, but the water “moves”. Add salt, monosodium glutamate and simmer for 3 hours. Place all the spices, leaves and lemongrass in a sachet (gauze bag). Add vegetables and simmer for another 60 minutes.
Remove the meat from the broth and strain the broth through a fine sieve. Cut the meat into thin slices and use when serving.
For pepper oil, beat all ingredients with a blender until an emulsion is formed and let steep for 12 hours.
To serve Pho Bo, pour hot soup into a soup bowl. Add cooked rice noodles. Place thinly sliced beef on top of the noodles. Garnish with cilantro, chopped chilies and a lime wedge. Add a drizzle of pepper oil if desired.
Garnish the finished soup with cilantro, chopped chili pepper and a wedge of lime. Add a drop of sesame oil if desired.