Peel the garlic and ginger, then roughly chop the spring onion and vegetarian pepper.

Blend the garlic, ginger, spring onion, vegetarian pepper, and black peppercorns into a coarse aromatic paste.

Cut the lamb shoulder into large serving pieces and rub it with the aromatic paste, mustard, paprika, turmeric, and salt.

Slice the 2 onions intended for the sauce and keep the remaining onion separate for the rice.

Heat the neutral cooking oil in a large pot over medium-high heat and brown the seasoned lamb on all sides.

Add the 2 sliced sauce onions and cook them with the lamb until deeply caramelized.

Pour in the 1 l water and add the bay leaf, then bring the pot to a simmer.

Cover the pot and simmer the lamb until tender, about 45 minutes.

Remove the tender lamb pieces and reserve them, then taste the broth and adjust the salt if needed.

Add the remaining sliced onion and the 420 g rice to the broth, then stir once to distribute it evenly.

Arrange the reserved lamb over the rice and cover the pot tightly.

Cook over low heat until the rice absorbs the broth and is tender, about 25 minutes.

Rest the thieb covered for 10 minutes, then serve the rice and lamb together on a large platter.