-
1
In a dish just large enough to hold the fillets in a single layer, mix together the brine: Combine the cold water, salt, and sugar and stir to dissolve.
-
2
Add the salmon fillets, making sure they are submerged in the brine.
-
3
Refrigerate for 15 to 20 minutes.
-
4
Meanwhile, heat the oven to 275 degrees F and arrange a rack in the middle.
-
5
Remove the fish from the brine and pat dry with paper towels.
-
6
Brush all over with the olive oil and place in a single layer in a baking dish.
-
7
Bake until just cooked through, about 20 to 25 minutes.
-
8
Meanwhile, cut the sweet potatoes (do not peel them) into 3/4-inch dice.
-
9
Place them in a medium saucepan and cover with cold water.
-
10
Add the onion, season with a few generous pinches of salt, and stir to combine.
-
11
Bring to a boil over high heat and gently boil until the sweet potatoes can be easily pierced with the tip of a knife, about 10 minutes total.
-
12
Drain the sweet potatoes and onions in a colander and let cool slightly.
-
13
Transfer the sweet potatoes and onions to a medium bowl, add the mayonnaise and orange zest, season with salt and pepper, and gently toss to coat, being careful not to break up the sweet potatoes.
-
14
Taste and season with additional salt and pepper as needed.
-
15
Heat the olive oil in a small frying pan over medium heat until shimmering.
-
16
Add the shallots and cook until just softened, about 2 to 3 minutes.
-
17
Add the oregano and cinnamon, stir to combine, and cook until fragrant, about 1 minute.
-
18
Add the orange juice and red wine and cook until the alcohol smell has cooked off and the sauce has been reduced by about half.
-
19
Taste and season with salt and pepper as needed.
-
20
Divide the warm sweet potato salad among 4 serving plates and place a salmon fillet on top.
-
21
Spoon the sauce over the salmon and garnish with a few sprigs of watercress or arugula.
