I think that 'very' should be removed; as it is implied with the word 'favorite'.

Hello cueyayotl, you are incorrect, See Wiktionary, https://en.wiktionary.org/wiki/very#English and the Cambridge Dictionary of English, https://dictionary.cambridge.or...y/english/very

As these sources show, "very" is used similarly in English both as an adjective and adverb . While the word can be used to enhance the degree or extent of somethng, such as in "very reasonable," "very far" or very intelligent". it has another meaning, revealed through its origin in old French, in which it meant "true" or "correct." It still bears that mening in 'English, as it does in German as well, cf the cognate "wahr."

First, please, consider that "favorite" in this sentence is an adjective serving as a noun. "my favorite [drink]." As a noun, favorite can take the adjective word very, meaning "true." Accordingly, "My very favorite [drink] has exactly the same meaning as "My true favorite [drink]."

Second, even if you prefer to perceive "favorite" as an adjective, (whereby "very" would be an adverb modifying an adjective) this usage is also completely proper. As the Wiktionary article points out, the adverbial "very" is properly used "to firmly establish the supremacy of a superlative." That brief article uses the example, "He tried his very best." "Best" is also, of course, a superlative. However, "very" does not attempt to form a superior form of best, but, rather "his true best."

This use of "very" is quite common, and I have heard it regularly in each of the seven decades of my life. I am not alone. as you can glean from the Wiktionary article, and the word's etymology, it has has been used this way for centuries.

Should you wish to view more examples, please consider these, all taken from the Cambridge Dictionary of English (cited above). In each instance "very" is used with a superlative, or an adjective incapable of forming comparative/superlative in English.

This is the very best chocolate cake I've ever tasted.
She always leaves her homework to the very last moment.
We now have our very own library in the village.
This is the very same (= exactly the same) place we sat the last time we came.

There are many examples of this usage on the web.

Google: "very favorite drink"

https://www.google.com/search?q...avorite+drink"

Very well, it is not something we would say in Texas, "very" is just not a word we would naturally use with "favorite", despite "true favorite" and "most favorite" being acceptable. Despite "very" being an adverb, you must remember that linguistics is not a natural science, and what may sound "logical" (as you explain yourself above) may not necessarily be correct in usage within a community. For us in Texas "very favorite" is as odd-sounding as "very excellent", which, by your logic above, should be correct.

If speakers of other variants confirm that this sentence is indeed natural sounding, despite it sounding odd to me, I will leave it as is.