How to Make It
Melt the butter in a medium sauce-pan. Add the leeks and cook over low heat, stirring, until softened but not browned, about 7 minutes. Add the wine and simmer until reduced to 2 tablespoons, about 4 minutes.
Remove the sauce from the heat and stir in the sour cream and then the caviar. Season with the lemon juice and salt and pepper.
Make Ahead: The recipe can be prepared though Step 1 up to 6 hours in advance and kept at room temperature. Rewarm before finishing.
Serve With: Pan-fried or poached halibut steaks, mahimahi or tilefish fillets; pan-roasted chicken breasts; baked potatoes; fresh pasta; steamed asparagus or artichokes