"how about spending" is correct and usable in written English.
You can use it when asking someone for their opinion about an activity, such as "How about spending the afternoon at the beach?".
Instead, how about spending that half an hour this evening actually cooking?
Or how about spending New Year in Gothic temple in Buckinghamshire, where all the rooms are circular?
Then a message from Mitt Romney arrived: how about spending a day with him on the campaign plane his wife calls "Hair Force One"?
How about spending the night out on the flats in an Airstream caravan sleeping two, that comes with a chauffeur/guide?
Someone asked me before the Rock and Roll Hall Of Fame 'Couldn't you just play with the original line-up again for one night?' And I said 'How about spending a night with your ex wife?
Instead of forcing the actors to perform a monologue or a whole scene from a play out of context, how about spending some money to make the equivalent of a movie trailer for each of the nominated plays, new and revived?
(Hey, neither do we! No big!) -- How about just spending some quality time with the boys?
How about infrastructure spending?
How about federal spending?
Well then, how about you spend sometime this weekend and make yourself a papercraft iPad.
Students: Tell us how you feel about spending time by yourself.
