Limes blended whole, peel and all, with water and sugar and then strained. The peel is what gives it its edge, and it has to be drunk soon after or it turns bitter. Five minutes, four glasses.
The whole lime goes into the blender, peel included, and that is the point of this version. The recipe's own note explains it: the peel gives the lemonade a bitter edge that most people find is exactly what makes it good. It is also why it has to be drunk quickly. Thirty seconds is enough in the blender. Longer and the peel breaks down further and the bitterness stops being an edge and becomes the whole drink. Then strain it immediately: leaving the pieces of peel sitting in the liquid does the same thing more slowly. Take the seeds out first. Lime seeds are properly bitter in a way the peel is not, and a blender will shatter them. Without a blender the method is simply squeezed juice, water and sugar, which is a milder and more familiar lemonade and keeps for longer.