Crush capers with the back of a spoon.
Melt 1tsp butter in a skillet over medium heat until butter foams lightly.
Sauté capers for 30 seconds in butter.
add lemon juice and white wine, bring to a simmer and cook, stirring frequently until liquid is reduced by 1/3-1/2. Usually around 3 minutes.
Remove from heat.
Salt and pepper to taste.
Stir in cold butter and chives (optional) stirring constantly until butter is completely melted and sauce is shiny and thick.