Going overseas always changes my eating habits in some way when I return. After visiting England, I started eating toast. After Scotland, I added tomato to some of my breakfasts. It isn’t just that I’m trying to hang on to the experience, though that's part of it. It’s also that the food I eat there seems more satisfying than my regular, American food. The effect so far that Italy is having on me is wanting more fruits and vegetables.
But perhaps what really made those meals great was the company. I had a tasty 2-course plus tiramisu dinner at a restaurant on my last night, and it was just an okay experience. By contrast, the mediocre meal I had in good company in Dorsoduro I enjoyed much more.
My best food advice for Italy is that if you’re eating alone, just grab something from a bar. If you’re eating with friends, choose a fixed-price menu at a restaurant and linger.