The phrase 'Reponse a tout' means Respond to everything [or all questions]. In the word-by-word translation, the noun 'reponse' means 'answer, response'. The preposition 'a' means 'to'. And the noun...
it means fully garnished, or all dressed
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It is a French term applied to food, pizza, subs etc. It is as indicated above, all dressed or the works.