Sayo's actually Filipino for "yours", so grab your best property lawyer and hit Marquette to find the bright-green truck, then have him negotiate the rights to the lunch that must clearly belong to you.
The first effort from a Phillipines-born chef, Sayo uses locally grown, seasonal ingredients to make "easy-to-grab varieties of gourmet food in the street", which translates to the rice noodles/chicken/chives Pancit Bihon (w/ egg rolls right in there!), and the soup-like Chicken Arroz Caldo: garlic & chive sticky rice topped with shredded chicken and a hard boiled egg, so you can ponder what part of this dish came first (weirdly, it was the chives!). For even easier-to-grab stuff, there're a la carte egg rolls served with a chili sauce they describe as "sweet" (a bit cocky for a first-time chef, huh?), and a trio of cucumber-sauce-topped soft tacos: pulled pork asado, pulled chicken adobo, and the Hawaiian with pineapple and pork.
Can't make it out to Marquette? Just get all your friends on board the Sayo-is-awesome train, then hit 'em up to cater your next party -- unless of course your lawyer's an overachiever, in which case they're already parked in your driveway.