A pleasant soup

I was inspired by Hanne Blank's piece about Chinese recipes which include corn and tomatoes to do a soup which worked out quite well.

32 ounces chicken broth (standard block of soup)
3 large tomatoes
4 ears of corn (don't throw away the cobs)
a tablespoon or so of chopped ginger
ounce or so of dried straw mushrooms
3 big garlic cloves, chopped
some Mean Ol' Rattlesnake Very Zesty BBQ Blend (Durango chili pepper, garlic, yeast, onion, paprika, hickory and mesquite smoke, black pepper, cumin, nutmeg, 90HU cayenne)
a very small amount (a little on the end of a knife) of ghost pepper powder
some salt
a pound of ahi tuna, chopped fairly thin, maybe 1/4 inch

Chop up the tomatoes and cut the corn off the cobs. Put them in the pot with the chicken soup and the garlic, ginger, corn cobs, mushrooms, spice mix, hot pepper (ghost pepper is the hottest pepper I know of, use with care), and salt. Simmer for maybe an hour.

When the soup is basically done, throw in the tuna, and bring it to a boil for a minute or two-- just enough to cook the tuna.

Take out the corn cobs.

Serves 4, or at least it looks like about 4 meals for me. It's surprisingly rich.

I don't think it has to be ahi tuna, but it should be fresh or frozen, not canned, or at least not standard American canned tuna, which tastes funny to me. Italian tuna would probably be all right, but it just needs to be warmed to soup temperature-- it's already cooked.

Any thoughts about what a vegetarian version would be? I'm guessing a rich vegetable stock, and maybe some sort of compressed tofu instead of the tuna.