1/4 cup Dijon mustard
1/4 cup vegetable oil
1/4 cup chopped fresh dill
3 tablespoons packed golden brown sugar
1/2 pound baby new potatoes, cut into 1/4-inch-thick slices
2 8-ounce salmon fillets
1 bunch mustard greens, trimmed, cut crosswise into 2-inch-wide strips
Preheat oven to 350°F.
Mix first 4 ingredients in small bowl. (Sauce can be prepared 2 hours ahead. Cover and let stand at room temperature.)
Place potatoes in small bowl.
Spoon 1 tablespoon sauce over and toss to coat.
Arrange potatoes in baking pan.
Bake 15 minutes.
Remove pan from oven; push potatoes to sides of pan.
Spread each salmon fillet with 2 teaspoons sauce and place in center of baking pan.
Bake until salmon is cooked through, about 18 minutes.
Meanwhile, place greens in large skillet.
Toss with 2 tablespoons sauce.
Stir over medium-high until wilted, about 4 minutes.
Divide salmon, greens and potatoes between 2 plates.
Serve, passing remaining sauce separately.