Comma Help

I believe this is the correct way:

"My decision to ask you, specifically, for a letter of recommendation...."

If what you are trying to say is,

"My decision to ask for a letter of recommendation from you specifically ...

then yes, it's fine. If that's not your meaning then what Shyanne Rae said May well be the ticket. More context would be helpful.

Like JTT my reaction, context might help

If the emphasis is on the speaker's decision to ask the listener specifically (rather than some other person) then I would place the commas thus:

My decision to ask you, specifically, for a letter of recommendation was based on my deep regard for your learning and judgement.