Raconter des salades means to tell lies/incredible stories. Nothing to do with food, it’s a figure of speech.

L’emploi de salade pour un mélange hétérogène au sens figuré est apparu au Moyen-Âge, employé semble-t-il pour la première fois dans le livre d’Antoine de la Sale La salade (1441), qui était une compilation d’histoires.

Ensuite en 1856 on trouve l’emploi de « salade » pour parler d’une réunion de choses confusément assemblées et on aboutit à la fin du XIX^e siècle à salade — le plus souvent au pluriel — pour « histoires mensongères ». Le Dictionnaire historique de la langue française (sld Alain Rey) dit 1901 (Aristide Bruant) sans toutefois citer d’exemple.

Tell tall tales means tell lies (although this should really be explained on EL&U)!

Salade started to be used in figurative sense in the Middle-Ages, it is said to have been used for the first time by Antoine de la Sale in his book La salade (1441), which was a compilation of stories.

It started to be used with the meaning of “tell lies/incredible stories” at the end of the XIX^th century. Attested in the Dictionnaire historique de la langue française to have been used in that sense in 1901 by Aristide Bruant but no example is given.

For the English meaning: a “tale” is nearly synonymous with “story”, whereas “tall tale” implies that there is more falsified in the story. It is used in both good connotations and bad connotations: “My grandfather told me tall tales of his youth” (which implies enjoyable but perhaps not 100% factual stories), or “She said that she was late because her car broke down, but that’s just a tall tale” (which is synonymous with “lie” in this case).

Sometimes “tale” means a completely fictitious story, like a fairy tale, whereas “tall tale” means a story based on fact but not entirely factual.