My flights from Bangkok to New York were on Korean Air. The flight from BKK to ICN, KE 658, was a 777-300ER. The flight from ICN to JFK was an A380. Because the business class seats on these two planes are the same and the service is very similar, the detailed review is presented in the A380 ICN to JFK post.
Update: More recent posts review flights in the fantastic Korean Air Prestige Suites on flights on a Korean Air 777-300ER and 747-8i. Korean Air Prestige Prestige Suites are one of the best business-class seats I’ve experienced.
Korean Air Prestige Suite
Check In Process
The Korean Airlines check-in counter at Suvarnabhumi Airport is located at Pier N. If arriving by taxi have the driver drop you towards the far end of the drop-off zone. At check-in the agent provided a pass to use the Premium (Priority) Lane through security and passport control. The security and immigration processes are the same as for non-premium lanes but lines are shorter.
The agents circle important information on the boarding pass and provide a map and directions to the lounge.

Korean Air Flight 658
Boarding
Korean Air Flight 658 was scheduled to depart BKK at 00:10 from gate G4.

After visiting the AF/KLM lounge on the F Concourse I arrived at the gate at 23:45. Boarding had started and there was no wait to get on the plane. To provide you with current info, here is my review of the newly remodeled AF/KLM lounge at BKK.
Korean Air 777-300ER
This 777-300ER has 291 seats — eight first class, 56 business and 227 economy. The 56 business class seats are arranged 2-3-2 in two cabins. The forward cabin with two rows of seats is the better cabin.

Korean Air 777-300ER Business Class Seat
My seat was 8F, an aisle seat in the center section of the second row in the forward business class cabin. While I prefer being by a window, the landscape cameras provided good views of takeoff and landing. It would be nice if U. S. airlines put exterior-view cameras on their planes. Fear of potentially enhanced legal liability maybe deterring the US airlines. Still I think the addition of landscape cameras on US carriers would be popular.

According to SeatGuru, these seats are 20.6 inches wide and have 74 inches of pitch. They recline to a full flat position. The configuration of 2-3-2 is far from ideal, but on this flight, the load in business class was light. The middle seat beside me was unoccupied.
Seat Features
A nifty feature is the way the tray table deploys from the console between the seats. There is no need to remove anything from the console to remove and set up the tray table.

Another great thing about Korean Air is that almost all of its long-haul flights within Asia have first-class cabins. That means on flights from/to many destinations in Asia, if booking a first class award ticket (or heaven forbid a paid one) passengers from the U. S. get two flights in first class instead of one in first class and one in business class.
That also means access to the Korean Air first-class lounge at ICN. The old Korean Air First Lounge in T1 was rather plain. Korean Air has now relocated operations to beautiful Terminal 2 which opened in early 2018 just in time for the Pyeongchang Olympics. If the improvements are anything like the improvements to the new Korean Air Prestige Lounge in T2, I’m anxious to see the new T2 Korean Air First Lounge.
Although Korean Air does not offer premium economy or extra legroom economy, even the economy seats on this 777-300ER are nice. They all are 18 inches wide and have 33 or 34 inches of pitch. They would be economy+ seats on US airlines!
Departure
Before pushing back, the Korean Air flight attendants offered pre-departure beverages and newspapers.
Takeoff was at 00:20. It was estimated that the flying time would be four hours and 40 minutes to travel 2,227 direct-route miles from BKK and ICN.
Amenities
Since it was a fairly quick flight, no pajamas were provided. The amenities provided at the seat were blanket, pillow, noise-cancelling headset, an eye mask, and slippers. There was no amenity kit.
To make up for the lack of amenity kits, Korean Air stocked the lavatories with dental and shaving supplies.
Meal Services
These were the menus for the flight:

Light Snack
Immediately after takeoff the attendants served beverages and a quick, light snack. Most of the passengers wanted to sleep as much as possible.


Those who wanted to sleep had about three hours to do so before the breakfast service began at 05:47 ICN time, one hour and 15 minutes before the scheduled arrival.
I had Laksa noodle soup. It was outstanding.

Fresh fruit followed.
Seoul/Incheon Arrival
We landed at ICN at 07:03 local in thick fog and arrived at Gate 22 at 07:15.

Overall Impression
In contrast to the flights to Bangkok on China Eastern, everything on this flight was top notch. It’s what Korean Air does. This airline lives up to its motto “Excellence in Flight.”
Other post on about this trip:
Delta CRJ 900 First Class, Charlotte, NC (CLT) to New York, NY (JFK) and a “Midfield” Takeoff
Delta Airlines SkyClub, New York, NY (JFK) Terminal 4
Quick Look, Korean Air Lounge, New York, NY (JFK) Terminal 1
China Eastern 777-300 Business Class, New York, NY (JFK) to Shanghai, China (PVG)
Transfer at Shanghai, China (PVG) and China Eastern VIP Lounge, Terminal 1
China Eastern 777-300ER Business Class, Shanghai, China (PVG) to Bangkok, Thailand (BKK)
Bangkok Hotel Review – The Sheraton Grande Sukhumvit, A Starwood Luxury Collection Hotel
JW Marriott, Bangkok, Thailand — The Best Hotel Lounge Buffet
Review — Air France/KLM Lounge, Suvarnabhumi Airport (BKK), Bangkok, Thailand