To speak bullshit to someone in a complimentary way. Commonwealth "arse" spelling preferred, as this expression probably has a London origin.

Usually expressed in the negative, by someone professing sincerity.
I'm not going to blow sunshine up your arse, Peter; you're the second-best of the surviving Doctor Whos.
by Fnordicle January 11, 2008
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Trump’s preferred Covid-19 cure
Vaccine? Who needs a vaccine? Blowing sunshine up your ass, that’ll get rid of that nasty corona. We have all the best sunshine here. UV, ultraviolet, you name it.
by Legitcures April 24, 2020
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