Choron sauce is a derivative of Béarnaise sauce. It is made by adding tomato purée or concassé near the end.
Depending on your preference, you may want to add diced tomato or tomato purée to the sauce to create Sauce Choron. If you want to add diced tomato, also known as tomato concassé, review the attached drill-down.
Once done, set aside.
Make the base sauce by following the method in the Béarnaise Sauce recipe on Rouxbe.
To make the derivative sauce Choron, simply stir in the tomato purée or tomato concassé into the finished Béarnaise sauce. Season to taste with salt and cayenne pepper. Stir in freshly chopped tarragon and serve.
Sauce Choron is typically served over fish.