Bring 2 quarts water to boil and add 1 teaspoon salt and 1 tablespoon red vinegar.
Add the mussels, octopus, and prawns
and boil for 1 minute. The prawns should redden and mussels should start to open. Add the squid
and the crayfish
and continue to cook over high heat until the squid is just translucent, about 1 minute. Drain
everything and place the seafood
all together in a warm bowl. Add the scallions, vinegar, olive oil, peppers, salt and pepper, and the mint, and toss to coat. Add the greens, toss again, and serve warm with lemon wedges and rock salt