Trying to remember the name of a certain drama (Ahjussi, younger lead heroine, more details inside)

Ok, so Im trying to remember the name of a drama, and these are the details I know:  The main character is a older male, and has a son, whom he lives alone with.  The Lead Heroine is a younger women, whom I believe calls the male lead by Ahjussi, and if I remember correctly, eventually turns out to be the Step Daughter of the male leads ex wife.  I believe the male lead worked in a restaraunt, but Im not sure about that one.

Thank you for any help or time spent on this.