PREHEAT oven to 230°C.
PLACE 1 sheet phyllo pastry on a cutting board; brush with 1 tsp melted butter. Top with 1 sheet. Cut to make 2 (22cm by 17cm) rectangles. Repeat with 2 more sheets.
LAY 1 (85g) skinless salmon fillet on short side of each phyllo rectangle.
BRUSH each fillet with 1 tbsp Dijon mustard; sprinkle with 1/8 tsp each salt and pepper. Roll up and place, seam-side down, on a bakingpaper-lined baking pan. Brush with 1 tbsp melted butter; bake for 12 to 14 minutes. (Salmon will be opaque throughout.)
WHISK 3 tbsp melted butter, 2 tsp fresh lemon juice and ¼ tsp each salt and pepper in a bowl. Pour over salmon and 450g steamed asparagus.