Melt butter in a small pan over medium-high or microwave in a bowl. Skim and discard foam. Pour butter into a measuring cup, leaving white solids behind.

Place yolks, lemon juice, water, cayenne pepper, and salt in your blender.

For Blendtec: Use SOUP button and let run full cycle. If butter is not hot, reheat. Press SOUP button, while motor is running, slowly pour butter through hole in lid.

For Vitamix and other variable speed power blenders: Start on speed 1, turn machine on then slowly increase to speed 10, then flip to high. Blend for 1 minute (and reheat butter if it's not hot). While motor is running, remove lid plug and slowly pour butter through hole in lid and blend for 2 minutes. Stop machine.

If the sauce is too thick, continue to blend while adding more lemon juice.

Pour into an ovenproof bowl. Stir in tarragon.

(Keep warm in a 200F (90C) oven for up to 15 min if not serving immediately. Whisk just before serving.)

All done! Enjoy!! Now take a photo, rate it, and share your accomplishments! :) Tag @BlenderBabes & #BlenderBabes