Though I think this may have been off the menu, it is definitely similar to some of the BTC beef options I've had on other flights. SQ is one of the few carriers where the in-flight beef is comparable to restaurant quality, so I would definitely suggest it for the meat-lovers!
Grilled beef fillet w/ thyme juice, buttered seasonal vegetables and potatoes.
HKG-SIN (Dec 2012, Business Class)
This was by far the best beef I've had in the sky. While quite similar in presentation to the others, the done-ness was superb and it was incredibly tender, juicy, and flavorful. I wish I had taken a photo of the inside to show how perfect it was cooked, but I just couldn't stop eating! I would be delighted to have this again, even in a restaurant.