sherry vinegar (or white wine vinegar), as needed to cover ingredients
½ cup heavy cream (optional)
8 tablespoons cold butter, cubed
Instructions
Combine shallots, tarragon, and peppercorns in a small saucepan and add vinegar just to cover ingredients. Bring to a simmer and cook until the liquid has mostly evaporated and only a couple of tablespoons of vinegar remain. Add cream, if using, and bring to a simmer. Slowly whisk in butter one piece at a time until fully incorporated. Strain out the solids and discard solids. Serve immediately or hold in a glass bowl over a pot of hot water to keep warm until ready to serve.
Recipe by Cooking With MicheleĀ® at https://cookingwithmichele.com/2012/11/creamy-tarragon-buerre-blanc-butter-sauce/