Poaching gently simmers fish in a flavorful liquid. Here the liquid is champagne, lemon and butter. The salmon has delightful flavor and served with the cool rosemary sauce it's a real treat. Don't use your best champagne, Cooks or Andre champagne works fine. Do use fresh rosemary. My last tip is that reduced fat sour cream doesn't have the same smooth texture that regular has so its best to use regular sour cream. I served this with roasted baby potatoes and roasted asparagus. Just toss them with olive oil, salt and pepper and roast in a 400 degree oven. The potatoes will take longer than the asparagus so put those in first. The asparagus will only need about 7-10 minutes.
For the Sauce:
1/4 cup sour cream
1/4 cup heavy cream
1 TBSP sugar
2 tsp Dijon mustard
1 tsp chopped fresh rosemary
For the Salmon:
1/3 cup unsalted butter, melted
3 TBSP fresh lemon juice
2 green onion finely chopped
1/2 cup champagne
2 lbs salmon fillets
Make the Sauce: Mix all ingredients for the sauce in a bowl. Whisk until smooth, cover and keep cool in refrigerator.
Make the salmon: Combine butter and next 3 ingredients in a large skillet. Bring to a boil over medium heat. Carefully add the salmon and reduce the heat to low. Cover and poach for about 30 minutes or until fish flakes easily with a fork. Remove the salmon from the liquid. Serve with the chilled sauce.