Grill the spices, peel the charred shallots, rinse everything thoroughly, and place in a cloth bag or stainless steel basket. Soak in boiling water for 15 minutes to reduce pungency and clean. Add the spice bag 3 hours before serving to ensure a fragrant but not overpowering aroma.

Simmer the marrow bones: Clean the bones, blanch in boiling water or roast for 20 minutes, then simmer for 6 hours. Add the spice bag and simmer for another 3 hours.

Boil the brisket and flank (cooking time: 1.5 - 2 hours, with some shrinkage after cooking). Remove, let cool, and refrigerate until serving. Soak the brisket and flank in cold water for 3-6 hours before boiling to make them white and fragrant. Blanch in boiling water, then boil.
Flank: meat near the front legs of the cow, with many tendons and connective tissues.
Brisket: belly part, thin and fatty.