Gather ingredients.

Place wine, lemon juice, cream, and shallots in a saucepan. Bring to a simmer over medium-high heat. Reduce heat to medium and let simmer until liquid is reduced by about 75%, 4 to 5 minutes.

Reduce heat to the lowest setting and whisk in 2 cubes butter. Keep butter moving until it completely melts. Add a few more cubes, whisking continuously so butter emulsifies into wine-lemon juice mixture.

Continue to add remaining butter, a few cubes at a time, until sauce has a thick, luxurious texture, 4 to 6 minutes.

Remove the saucepan from heat. Season with cayenne pepper and salt. Garnish with chopped chives if desired.