Ready in 45 minutes
Very similar to hollandaise sauce!
Make the bearnaise reduction first. In a small saucepan, combine the shallots, tarragon, pepper, vinegar and wine over medium-high heat. Bring to a simmer and cook until reduced by half. Remove from heat and set aside to cool.
Pour the reduction into a blender. Add the egg yolks, salt, pepper and cayenne. Mix on high for 1 min. Heat the butter in the microwave until boiling.
With the blender running, add one third of the butter in a slow steady stream. Once it emulsifies, turn the blender speed up to high and add the remaining butter. Set aside in a warm spot to hold the sauce.