As fidgetbones says, don't cut the entire plant clear to the ground. Cut the outer leaves off but leave the heart alone. Alternatively, I've cut off the entire top off a row about two inches from the ground of the 'cut and come again' varieties, and they grow back without issue.
Posts
Some are cut and come again, just buy the right seed, and sow plenty of it, my kids love it.
If you cut the leaves and not the growing point, they will regrow. I use scissors, and sow a fresh tray every three weeks through the summer.
As fidgetbones says, don't cut the entire plant clear to the ground. Cut the outer leaves off but leave the heart alone. Alternatively, I've cut off the entire top off a row about two inches from the ground of the 'cut and come again' varieties, and they grow back without issue.