Preheat the oven to 220 ° C (th. 7/8).
Peel and cut the sweet potato into cubes and mix them with 2 tablespoons of olive oil and salt.
Spread them evenly on a baking sheet lined with baking paper and bake for about 30 minutes.
Prepare the spice blend: combine all the ingredients in a small bowl and mix well.
Wipe the trout fillets with a paper towel.
Liberally coat the flesh side with the spice blend.
Heat a skillet over medium heat.
Pour 1 drizzle of olive oil, then place the fillets, skin side up.
Cook for about 2 minutes so that they become crisp without being burnt.
Turn and cook for 2 to 3 minutes, skin side down.
Just before serving, mix the arugula with the juice of half a lemon (keep the rest in quarters to serve with the fish) and a little olive oil, season.
Serve the fish with the salad;
grilled sweet potatoes and a few lemon wedges.
A recipe from Zoé Armbruster, food stylist and Blaise Gargadennec, food photographer. Zoeandblaise.com.