I think, in particular, this is a play on words revolving around "a colpi di fulmine" - the Italian expression for the "thunderbolt" or "love at first sight".

Given the context I think either of these suggestions could work.

Chocolate brownie with two scoops of vanilla and hot fudge sauce please :o)

a colpi di ... generally means to insist on something using a certain method/tool when doing so in order to persuade or make someone do something see below

• Fig.: con insistenza, a forza d'insistere, utilizzando più e più volte la stessa cosa come strumento di propulsione o di convizione. Vale per un utensile come per un argomento o altro.

So you could say that the "persuasive tool" in this courtship was ice-cream so being bowled over with ice-cream (play on words also on the bowls of ice-cream they were enjoying or discussing) and metaphorically speaking, being won over, dazzled, pleasantly surprised by the girl's beauty, conversation or whatever it was that made him fall for her.

It's a similar idea to the Italian -"mi ha fatto colpo"





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Note added at 5 hrs (2017-02-08 16:51:41 GMT)
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the Italian a colpi di gelato is like saying she wooed me with ice-cream (her seductive tool)

Trying to be creative. I don't know if English play on words could really use the same subtle and suggestive imagery (as colpi), so I think just stating the obvious could be a solution.

""Ice cream: The flavour of LOVE" is possible too, but I think that "attraction" sounds less corny.

You coyk