Soak the toast in water and squeeze it.
Whisk with the nuts, peeled garlic cloves, oil, pepper, salt, vinegar and 1 to 2 tablespoons of cold water until the sauce is nice and creamy.
Serve in a sauce bowl with grilled fish or fried zucchini slices.
This sauce tastes even better when prepared with walnut oil or possibly sherry vinegar.
Tip: The flesh of young, small zucchini is much more tender than that of larger ones.