Place all the ingredients for the spice blend on a baking tray and roast for 5 minutes on low temperature, until aromatic. Grind in a coffee grinder and store in an airtight jar.
To make the chermoula:
Chop the tomato, onion and herbs finely. Add remaining chermoula ingredients, mix.
To make the tagine potatoes:
Saute the onion and add the garlic. Add the potatoes and Moroccan spice and cook 3 minutes uncovered. Add the remaining ingredients, cover and cook over low heat 30 minutes or until potatoes are tender.
To make the tagine:
Season fish fillets. Sprinkle each fillet with a pinch Moroccan spice and dust with flour. Heat oil in a pan over medium heat. Cook the fillets lightly on each side. Deglaze the pan with the wine.
Share the 4 tablespoons chermoula among the fillets and cook another minute or two, until almost cooked.
Put a quarter of the tagine potatoes in each serving bowl and place a fish fillet on top. Add the preserved lemon, parsley and mint and pour the pan juices over. Top with toasted almonds and serve.