I’ve only seen it the first way. My daughter ate at an Italian place in Boston and said the menu spelled it the second way. Is there an Italian in the house?
I agree that only have seen it the first way, but wikipedia says either.
Interesting side note. Spelled saltinbocca in earlier Google book hit.
Yeah, my daughter mentioned Wiki, but I was hoping for an HTG Italian to set it straight.
Trouble is, you’d need a 100 year-old Italian. 
Further checking shows recipes under both spellings on the intertoobs, although Google wants me to correct ‘saltinboca’ to ‘saltimbocca’. Perhaps “Cecil” could nail it down.
Trust me on this. Cecil would probably ask for my help.
I’ve always heard and seen “saltimbocca”.The “saltinbocca” is most likely because whoever is writing the menu knows enough to know that “in” has the same meaning in Italian and English and the name of the dish means something like “jumps in the mouth”. But I remember enough of my Italian to remember that sometimes sounds are eliminated or changed for ease of pronunciation.
Not so much jumping inside the mouth as jumping into the mouth.
The last thing is what I think: in some dialects, at least, there would be no difference in the two pronunciations.
Also, it’s not like English doesn’t do the same thing. How many people do you know that say imput for input? Heck, in a century or two, I bet it will be be spelled imput–the same change that happened for most other in- prefix words where it’s easier to say im- instead.
I think this is right. You commonly see the “n–>m” shift in people’s names, like Giampaolo (the combination of “Gian(ni),” from Giovanni, and “Paolo”), where the original “N” is next to a “P” or “B”. You can spell the word either way – in this particular example, googling “Giampaolo” gets 10,700,000 hits, and “Gianpaolo” gets 4,140,000 hits.