Cut the slices of tuna into cubes.
Mince the onion, cut the garlic into thin slices.
In a bowl pour the mustards, turmeric, ginger, garlic, thyme, fenugreek and oil to obtain a homogeneous mixture.
In a wok saute the fish over high heat to color it.
Deglaze with vinegar, add the onions and simmer while stirring gently.
Add the spice mixture and the oil and stir gently, cooking for another 5 minutes.
Season with salt and pepper and add the finely detailed peppers.
Bon appétit de
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