Step 1

Bring lemons to room temperature, then roll firmly against the counter to soften their rinds. Halve and juice; pour juice into a sealable container and refrigerate. Cut rinds into 1-inch chunks. Toss with sugar in a large nonreactive mixing bowl, cover tightly with plastic, and let stand at room temperature, stirring once every 45 minutes or so, until sugar has completely dissolved, about 3 hours. (You can let the mixture stand up to 12 hours, if desired.)

Step 2

Add water and 8 ounces (1 cup) of reserved lemon juice (see note). Stir well, then strain through a nonreactive fine-mesh strainer or piece of cheesecloth into a glass or ceramic container. At this point, the concentrated lemonade can be refrigerated for up to 1 week.

Step 3

When ready to serve, pour lemonade over ice and adjust to taste with additional water or lemon juice, depending on personal preference; bear in mind, though, that the lemonade will be diluted as the ice melts. (You will likely have some fresh lemon juice left over, which can be reserved for another use, though exactly how much you have will depend on how much you added to adjust the lemonade.)