It was just the right place, quiet and cool with chairs and tables, at just the right moment.
Want more practical info about the cafè? Here's the official civic web site (the museum belongs to the city) which isn't in English--booooo!--but it does have the phone number and hours (the cafè is inside the museum, so observes their hours): http://www.comune.milano.it/dseserver/webcity/documenti.nsf/0/1080BA0850607AF7C12570B300371910?opendocument
As usual, all pictures are mine, and are for your personal non-commercial enjoyment. The first photo of the Renoir exhibit in nearby Pavia was a wonderful stroke of luck: shade from an overhanging tree perfectly aligned with the shade of the lovely lady's umbrella. Fun!