Does anyone in this town remember the Guggy's surprise cake? At this point, we're pretty sure we dreamed the whole thing up, but we have vivid memories of birthday cakes purchased at Guggy's coffee shop (there was one at Scottsdale Fashion Square, back in the day when that was still an outdoor mall) made of thick, rich layers of cake layered with sweet frosting and some sort of nutty, chocolaty filling ? the "surprise." Fantasy or not, we've fulfilled our longing with the Mexican version of the surprise cake ? tres leches cake at the bakery at La Tolteca. You can buy a whole chicken at the market at La Tolteca, or a great burrito at the takeout counter, but our favorite spot is the bakery, where the tres leches cake is sweet and rich, the cake itself almost creamy, layered not with chocolate and nuts but with vanilla icing and fresh strawberry or peach filling. Tres leches stands for "three milk," indicating the cake's key ingredients: condensed milk, evaporated milk and whole milk. We're sure Guggy's didn't pay quite as much attention to detail (what difference did our young palates know?), and we're happy as adults to celebrate our birthdays from here on with La Tolteca's specialty.