A Mayonnaise-Based Sauce Commonly Served With Fish

This page is the CodyCross answer for the clue below from Café, Group 1337, Puzzle 3 (Vegetable Frittata).

Question is: A Mayonnaise-Based Sauce Commonly Served With Fish

and the answer is: TARTAR

Word Meaning:

TARTAR — A red compound deposited during wine making, mostly potassium hydrogen tartrate; wine stone — a source of cream of tartar.

Definitions from Wiktionary.