Grate zest from the lemons, then squeeze out the juice.
Beat butter and sugar until blended. Add eggs one at a time.
Gradually add lemon juice, mix in zest. Transfer to a saucepan.
Cook over medium-low heat, whisking constantly for 14-16 minutes.
Transfer to a bowl, cover with plastic wrap, and chill for 2 hours.
Notes :
Properly drain the cucumber to remove excess moisture.
Chill for at least 30 minutes before serving to enhance flavor.