Halve the lemons lengthwise from stem to base or halway (easier). Squeeze out the juice and measure 1 ½ cups to be used for the sorbet. Save the remaining juice for other uses. Use a spoon to remove the pulp and pith from the inside of the lemon shells and set aside.
Combine the sugar and water in a pot and bring to a boil. Stir occasionally. When the sugar dissolves, turn off the flame and pour in the lemon juice. Mix to combine, and transfer the flavored water to a container or a 9x13-inch pan. Freeze overnight or until it is completely frozen.
Cut the ices into chunks. Place half the chunks of ice in a food processor and blend until ices turns into a white and fluffy sorbet. (Freeze the remaining half of ices blocks while you work since it melts very fast.) Working quickly, scoop sorbet into empty lemon shells and place them in a single layer on a cookie sheet or inside a large container. Freeze. Repeat with second half of the ice blocks.
Note: If you repeat the freezing/blending process a second time before filling the lemon shells, the sorbet will be whiter and fluffier.
Tip: On day 1 After I squeeze out the lemon juice, I store that empty lemon shells in the freezer in a bag to prevent their spoiling until they are ready to be filled.
Recipe by Between Carpools at https://betweencarpools.com/lemon-ices/