Banana-Sour Cream Pie

This is very quick to put together (no baking!) with items that many people may have on hand, and it's very tasty--rich, with a good banana flavor. Be sure to use a fully-ripe banana or two for this because an underripe banana will ruin the flavor (I know from experience). I have used mascarpone in place of some of the cream cheese and that makes for a very excellent variation. Be sure to whir everything together until perfectly smooth. If you only mix it by hand, it will still have some cheese lumps in it, which isn't so nice.