BLENDER HOLLANDAISE: This version is denser than regular hollandaise. Prepare the butter as described above. Combine the yolks, lemon juice, and water in a blender and blend for 2 seconds. With blender running at medium speed (if speed is too high, sauce will splatter), add half of melted butter in a slow stream through hole in lid. Add 1 tablespoon warm water to thin sauce, then continue slowly adding remaining butter (leaving milky solids in bottom of pan). Thin sauce to the desired consistency by whisking in additional warm water (1 to 2 tablespoons), then whisk in salt and pepper.