Sunflower, the dual-entrance Vietnamese restaurant that straddles the corner of 16th and Valencia, has long been a favorite amongst Missionites for its solid renditions of classics like garlic noodles and imperial rolls, not to mention reasonable prices that have held firm despite Valencia's increasing gentrification. But now, Sunflower is mysteriously shuttered, with only a sign on the door reading "We are closed until further notice. Sorry for the inconvenience." A call placed to the restaurant was answered by a voicemail box with an identical message. A staffer at Sunflower's sister location in Potrero Hill, which remains open, refused to comment on why the Mission location was closed, or when it might reopen. Given the numerous businesses closing on the surrounding blocks due to massive rent hikes, things don't look positive.