Flew CX257 on Dec 1 and CX250 on Dec 4. Didn't take pictures of the menu but here's my general feedback. Both of these flights were operated with the new service.
CX257: By far the best CX J meals I've had. Since it was a day time flight, there wasn't really a rush to serve all the food. Service wasn't that fast, but not noticeably slow either. Flight started off with breakfast, so I got the Chinese option (Pork & scallop congee w/ assorted dim sum) with a Cathay Delight. The congee was pretty flavorful with the marinated pork and ginger, but I found no scallop at all. I have pretty good eyesight, so unless they were baby scallops that were shredded completely, I can pretty confidently say there wasn't any. No real complaints there though; scallop wouldn't really add much to the dish for me. However, that was also the best Cathay Delight I ever had. It was especially minty which made it lighter and more refreshing. Was disappointed that I supposedly missed the Oriental Breeze (my preferred drink) by a day and that they didn't have cranberry juice on board. Drink selection in general was very limited.
Lunch was very impressive. The pork starter (garlic-marinated strips of pork thinly sliced served cold with cucumber slices) didn't come with much sauce on the plate, but it came with chili sauce (辣椒酱). I added a ton of chili sauce to it before I got much flavor out of it... I'm not sure if my taste buds were that badly affected by the altitude or if the sauce was weak, but it ended up being a really nice appetizer once I knew how much sauce to add. I ordered the beef tenderloin with polenta (and some veg, I forget) for my main course. The beef was cooked to a perfect medium rare (biggest wow factor) and there was ample sauce. The polenta was delicious too. My dessert was the most memorable part of my dining experience though. I had a bubble tea inspired pudding (珍珠奶茶布丁) and it tasted just like the real thing. The tapioca balls were made out of sago instead so they weren't really hard at that cold temperature, so it was well thought out. Great job CX!
CX250: I was quite excited for this flight knowing that I would be getting the new service again. However, London catering was very disappointing. Before I get into that though, there was a massive line for check-in when I arrived. 4 counters working in total: 2 economy, 1 business, 1 first. The economy line was absolutely massive – at least 50 people. I felt quite bad for them. Anyways, as for the food. The flight started with dinner. The starter was a dish of prawns and sweet chili sauce served with some kind of tofu-like bread. I just ate the prawns and sweet chili sauce. I chose the pan-fried chicken breast with carrots and spinach. Chicken was dry (I should've known, but my experience on 257 convinced me to stick with the chicken which sounded like the better option on the menu). Carrots and spinach were unappetizing too. I usually like both of those veg but it just didn't taste good. I didn't try dessert because I wasn't hungry after spending hours in the lounge before the flight anyway, but my neighbor got a chocolate mousse that looked pretty good.
Breakfast was also mediocre at best. Again, I got the chinese option, but the congee was really quite bland (still finished it) and the stir-fried egg noodles was strangely dry. I tried a cold-pressed melon juice since the Cathay Delight on this flight was really inferior to the outbound flight, and that also disappointed. However, I think that was more about my personal opinion than the quality being poor.
In essence, great HKG catering on the outbound flight, but poor LHR catering. Considering how important of a destination LHR is for CX, I hope they get it right soon.