Foraging for wild mushrooms and celebrating crayfish parties are two dear Finnish traditions of mine. This dish pays homage to both.
Start by (sending your better half) collecting mushrooms. Mine brought me chanterelle, penny bun and birch bolete, but you can use any edible fungi you find. Then separate the tails and tomalley from the crayfish. Turn the rest of the crustaceans into a delicious stock. Alternatively, you can use crayfish tails in brine and a store-bought beurre de homard. Briefly sauté the crayfish tails and your mushrooms with chopped shallots in olive oil. Season with fleur de sel, lemon juice as well as fresh lemon thyme and oregano.
Toast slices of chiabatta and coat them with crayfish tomalley (or beurre de homard). Top with the sautéed crayfish and mushrooms and decorate with oregano blossom.