The place is called Lemon Tree. It's a Hong Kong style chinese joint in a strip mall on Fair Oaks between the 110 and Mission, the same strip mall as El Pollo Loco and Subway. You could drive by a thousand times without noticing it.
They have dozens of slush drinks that are made from fresh fruit. Kiwi and Watermelon have been simply outstanding so far. These are not made with smoothie powder or cream, really just fruit and juice and blended ice. Very light and refreshing.
They also have boba drinks which I haven't tried. They also have a typical menu of chinese food, and to me it is better than most but not worth going out of your way.
Note: Don't get confused. There is another fast food chinese place in the same strip mall a couple doors down. It's awful.