Here are my faves from each cuisine:
Japanese
The pure elegance that is sashimi, whether toro, hamachi, maguro, salmon
And of course Nigiri and misc roll sushi
Sukiyaki
Simple pork or shoyu ramen
Deep fried hamichi cheeks
Grilled anago / unagi
Kobe beef shabu shabu
Steamed, then pan fried gyoza with ponzu sauce
Vietnamese
Pho Tai with purple basil, lime, some siracha, and a dash of hoisin - pure comfort food, nothing better on a cold night
Slow simmered short-rib beef stew, infused with 5-spice, with fresh baguette
Iced coffee over sweetened condensed milk (AKA "crack")
My fave sandwiches - Grilled, sweet lemongrass chicken, with cilantro, picked radish and carrots, mayo, and Magee sauce, on a fresh baguette.
Chinese
Too many to name...
Black bean, deep fried catfish or whole crab
And the boiling, scalding, explode in your mouth dumplings
And then there is the brilliance of Thai food
My fave Asian cuisine
No other culinary tradition or style matches Thai food for the genius balancing of sweet, sour, salty, bitter, and fatty flavors
When you perfectly balance coconut milk, fish sauce, tamarind, gingers, garlics, galangal, palm sugars, various curries, etc, you're bound to make fabulous food.
Indian food is similar in character, but not quite as sweet, which doesn't lend to maillard, blackend, grilled flavor profiles.
Speaking of grilled flavor... Korean bulgogi and kalbi kicks all kinds of ass
Hundreds of different kinds of kim chee
Bi bim bop
Most brilliant, underappreciated cuisine? Mexican. Seriously, it goes way beyond tacos, burritos, and the like. Do some research and read up on Rick Bayless's books and recipes.
Posole is my #3 comfort soup, after Vietnamese Pho, and Japanese Ramen.