I had this in Okinawa and became addicted! When papaya are cheap, I make this dish! It's also great for bentos!
Whenever I make this at home, my husband very happily eats it.
Papaya fruit is good too, but please also appreciate this vegetable type papaya.

Since this is stir-fried and then simmered, the ingredients become tender, but if you want to keep the crunchy texture of the papaya, you don't need to simmer it. Just add some dashi granules when stir-frying.
Adding the whole can of tuna as-is creates a rich flavor, but you can adjust the amount of soy sauce and other ingredients if you want. Recipe by Tedakankan