I’m not a vegan and never will be, but I do have many friends who are and when I can find a recipe for them it os always a pleasure to put it online!
Now beans, especially fermented beans/natto/納豆 comes with a lot of healthy ingredients for such a priority.
Rice (you may use it whole of course and tea have also plenty!
Chazuke/茶漬け is a Japanese way to accommodate cold leftover steamed rice by basically warming it up through pouring hot tea over it. A cold version is also possible, especially in summer!

INGREDIENTS (I leave the proportions to your appetite!):

Cold steamed rice (leftovers)
Hot tea
Natto
Soy sauce
Chili pepper powder
Finely chopped scallions/white leek
Optional: sesame oil, grated ginger, etc.

RECIPE:

Pour some plain natto inside a bowl.

Mix/stir natto with chopsticks or fork long enough to see natto completely linked with sticky filaments. As a criteria stir it a hundred times!

Season it with soy sauce (and sesame oil as an option) and chili pepper powder and stir.

Add finely chopped scallions/white leek (and grated ginger as an option) and mix well.

In a bowl place enough cold teamed rice and natto on top.
Pour hot green (or oolong) tea over the rice up to the top of the ice.
For the cold version pour ice-cold tea.
Enjoy!

So simple and healthy!

RECOMMENDED RELATED WEBSITES

Shop with Intent by Debbie
BULA KANA in Fiji
Kraemer’s Culinary blog by Frank Kraemer in New York,Tokyo Food File by Robbie Swinnerton, Green Tea Club by Satoshi Nihonyanagi in Shizuoka!, Mind Some by Tina in Taiwan, Le Manger by Camille Oger (French), The Indian Tourist, Masala Herb by Helene Dsouza in Goa, India, Mummy I Can Cook! by Shu Han in London, Pierre.Cuisine, Francescannotwrite, My White Kitchen, Foodhoe, Chucks Eats, Things that Fizz & Stuff, Five Euro Food by Charles,Red Shallot Kitchen by Priscilla,With a Glass, Nami | Just One Cookbook, Peach Farm Studio, Clumsyfingers by Xethia, PepperBento, Hapabento, Kitchen Cow, Lunch In A Box, Susan at Arkonlite, Vegan Lunch Box; Tokyo Tom Baker, Daily Food Porn/Osaka, Only Nature Food Porn, Happy Little Bento, J-Mama’s Kitchen, Cook, Eat, Play, Repeat, Bento Lunch Blog (German), Adventures In Bento, Anna The Red’s Bento Factory, Ohayo Bento,

Must-see tasting websites:

-Sake: Tokyo Through The Drinking Glass, Tokyo Foodcast, Urban Sake, Sake World
-Wine: Palate To Pen, Warren Bobrow, Cellar Tours, Ancient Fire Wines Blog
-Beer: Another Pint, Please!, Beering In Good Mind: All about Craft Beer in Kansai by Nevitt Reagan!
-Whisky: Nonjatta: All about whisky in Japan by Stefan Van Eycken
-Japanese Pottery to enjoy your favourite drinks: Yellin Yakimono Gallery

Non gastronomy must-see sites by Shizuoka Residents

HIGHOCTANE/HAIOKU by Nick Itoh in Shizuoka City