Spicy Vietnamese Beef Noodle Soup (Bún bò Huế)

Ingredients

• 4 pounds pork feet
• 2 pounds beef shank
• 2 shallots divided
• 6 stalks lemongrass divided
• 5 tablespoons oil tbsp, divided
• 1 tablespoon chile flakes tbsp
• 1 tablespoon lemongrass tbsp chile, sate
• 2 boxes bun bo hue bouillon cubes
• 11 cups water
• fish sauce to taste
• salt to taste
• 2 packages vermicelli noodles large
• 1 bunch cilantro finely chopped
• 1 bunch scallion finely chopped
• 1 bunch Vietnamese coriander or rau răm, finely chopped
• 1 banana blossom sliced thinly
• 2 limes quartered
• lemongrass chile, sate, to taste optional