Chef Stephen Trojahn traded the world of fine dining (he formerly oversaw the kitchens at Cosmos and Bradstreet Craftshouse in the Graves Hotel) for the more cramped confines of Gastrotruck. The switch is good news for downtown St. Paul diners, as Trojahn treats street eats with four-star seriousness, creating thoughtful flavor pairings from seasonal produce and local, naturally raised meats, and serving them in compostable packaging. Sliders are a main component of the Gastrotruck menu, but they're a serious step up from their White Castle cousins. The mini-burgers come two to an order for $6 to $8, in several variations, including the likes of grass-fed beef meatloaf with tomato-bacon jam, smoky pulled pork with red cabbage slaw, and black bean cakes with sour cream and sprouts. The sliders disappear in about four bites, but they're carefully crafted, with the details done right, from the griddled bakery bun to the house-made pickles set out on the truck's condiment rail. Trojahn sneaks a few healthful tweaks into his fare: a side of wheatberry salad, penne, and melted cheese is made with whole-wheat noodles; potato salad substitutes a lighter yogurt dressing for mayonnaise. Order those items and it's easer to justify indulging in the cinnamon-raisin bread pudding with rum-caramel sauce, or better yet, the white chocolate panna cotta or the banana-cake whoopee pie with whipped peanut butter filling. For those looking to tote some goodwill back to the office, the spicy-sweet caramel corn is easily sharable.