I've been through all the entries tagged food, and can't find this. Sometimes I wonder if I dreamt this fic.

It's set mid-season three. Everywhere that Sam and Dean go, Dean makes a point of taking Sam to specific eating establishments, and sometimes to houses of people he knows. It takes Sam a while to realise that Dean is introducing him to the people involved so that when he is gone, Sam will be looked after.

Does this ring bells for anyone? It might have been part of a longer fic, and not the focal point.

ETA; Found, The Best Sauce by uschickens, see link in comments.