La menta no solo va bien en el té, sino también en una ensalada con pepino.

Yes. Ir bien literally means to go well, but in sentences like this it works like to go well with / to suit / to work well in.

So:

• La menta va bien en el té = Mint goes well in tea
• not literally that the mint is physically going somewhere, but that it is a good match

This is a very natural way in Spanish to talk about food combinations.

You could also hear:

• La menta queda bien en el té
• La menta combina bien con el té

But va bien is simple, common, and idiomatic.

It means not only ..., but also ...

So the structure is:

• no solo X, sino también Y

In this sentence:

• La menta no solo va bien en el té, sino también en una ensalada con pepino.

That means:

• Mint goes well not only in tea, but also in a salad with cucumber.

It is a very common Spanish pattern. A few more examples:

• No solo estudia español, sino también francés.
  He/She studies not only Spanish, but also French.

• No solo es barato, sino también bueno.
  It’s not only cheap, but also good.

Because no solo ..., sino también ... is a fixed contrast structure in Spanish.

After a negative idea like no solo, Spanish normally uses sino to introduce the second part.

So:

• no solo ..., sino también ... = correct
• no solo ..., pero también ... = not the usual standard structure

Very important: sino is one word here.

Compare:

• sino = but rather / but instead / but also in this kind of structure
• si no = if not

So in your sentence, it must be sino también.

Because té with an accent means tea.

Without the accent, te usually means you as an object pronoun:

• Te veo. = I see you.

So:

• té = tea
• te = you

The accent helps distinguish two different words that would otherwise be spelled the same.

Spanish uses articles more often than English, especially when talking about things in a general sense.

So:

• La menta = mint in general
• El té = tea in general, or tea as a category/drink

This is very normal in Spanish:

• El café es amargo. = Coffee is bitter.
• La leche tiene calcio. = Milk has calcium.
• La menta va bien en el té. = Mint goes well in tea.

English often drops the article in these general statements, but Spanish usually keeps it.

Because the prepositions are doing different jobs.

• en el té = in tea
• con pepino = with cucumber

Here, en tells you where the mint works well:

• va bien en el té
• goes well in tea

And con describes the kind of salad:

• una ensalada con pepino
• a salad with cucumber

So the sentence is not saying mint goes well with cucumber directly, although that idea is implied. It is saying mint goes well in a salad that contains cucumber.

Because una ensalada con pepino means a salad with cucumber in a general, non-specific sense.

• una ensalada = any salad / a salad
• la ensalada = the salad, a specific one already known in context

Here the sentence is making a general point about possible uses of mint, so una is more natural:

• La menta no solo va bien en el té, sino también en una ensalada con pepino.

That means mint works well in tea and also in a cucumber salad, not necessarily one particular salad.

Yes, that is also correct and very natural.

Compare:

• La menta no solo va bien en el té, sino también en una ensalada con pepino.
• La menta va bien no solo en el té, sino también en una ensalada con pepino.

Both are good. The difference is mainly one of focus and rhythm.

• In the original, no solo comes earlier and highlights the whole idea from the start.
• In the second version, va bien comes first, and then the contrast focuses more clearly on the two places: en el té and en una ensalada con pepino.

Spanish is often flexible with this kind of word order.

Yes, solo without an accent is correct.

Current standard Spanish normally writes:

• solo = alone / only
• without an accent in both cases

So in your sentence:

• no solo ..., sino también ...

that spelling is standard.

You may still see sólo in older texts or from writers who prefer it to avoid ambiguity, but modern standard spelling generally uses solo.

In Spain, pepino means cucumber.

So:

• una ensalada con pepino = a salad with cucumber

That is the normal everyday word in Spain.

A learner may ask this because some food words vary across Spanish-speaking countries, but pepino is perfectly standard in Spain.

It specifically points to a salad with cucumber.

The phrase con pepino modifies ensalada, so the meaning is:

• a salad that has cucumber in it

So the sentence is not making a broad statement about all salads. It is giving one example of another place mint works well: a cucumber salad.

If Spanish wanted to say mint goes well in salads in general, it could say something like:

• La menta va bien en las ensaladas. = Mint goes well in salads.

Yes, very much.

Spanish often uses simple verbs like ir bien, quedar bien, or combinar bien to talk about flavors and ingredients.

For example:

• El limón va bien con el pescado.
  Lemon goes well with fish.

• La albahaca va bien en la pasta.
  Basil goes well in pasta.

• El yogur combina bien con la miel.
  Yogurt goes well with honey.

So this sentence sounds natural and idiomatic for talking about what ingredients work well together.