Though I have not been to Singapore (but would like to, that is why I go to this website) I think I can give you some general info that will help.
Take a short class (non-credit is the best so the focus is on learning opposed to a grade) in both and see if you still like both. I did this with Thai cooking and have developed an interest and had considered giving up engineering to become a chef.
The biggest reason, I haven't is though I like cooking a few dishes for friends/family; I haven't mastered the art of juggling cooking many, many dishes at the same time. See if you can do this by cooking for maybe a dozen people at the same time, a wide variety of dishes and trying to get them the food all around the same time.
Regarding hours, I completely agree with Ines that an electrican would have more regular hours. Well, if you still like both take this to your advantage. Trying some catering on weekends/nights when it wouldn't conflict with being an electrican.
Both have the potential for good $, and job advancement depending on what you want.
here is a proposed progression
Electrician -> shop foreman -> own electrician contract business
or after getting hands on experience with electricity, go back to school and maybe become electrical engineer
Prep Chef -> Assistant Chef -> Executive chef/ food critic/ cooking instructor
So, there are a lot of great possiblities.
If I can help further let me know