Trim green tops and root ends from leeks; slit vertically into quarters, leaving 1/3 inch intact at root end. Separate sections and wash under cold running water; drain well.
In 10-inch saute pan, melt butter over medium heat. Add leeks and cook 2 to 3 minutes, stirring often, until leeks are wilted. Stir in wine, arrange salmon on leeks, sprinkle with salt and pepper.
Reduce heat to low, cover and cook 5 minutes. Sprinkle cheese over salmon, cover and cook another 3 to 5 minutes or until salmon is opaque around edges and firm, and cheese is melted.
Transfer to warm dinner plate with broad spatula and serve immediately.
