Picture this: It’s one of those brutally hot days, when the Texas air is as still and thick as homespun cream. Far in a South Austin field, behind a row of trailers, there’s a girl. She’s standing in a tiny patch of shade, holding something in each hand. Closer, closer now. We don’t want to scare the wildlife. Now you can see the outline of the huge, fresh-baked cookies, the ice cream sandwiched between them melting faster than an ice sculpture in August, dripping down her wrists and onto her milk-studded, poorly chosen black T-shirt. On her face there’s an expression of pure, unadulterated five-year-old joy. And more ice cream and cookie spackle than there are summertime freckles. Don’t judge. So what if I had two ice cream sandwiches? I dare you to brave Coolhaus and not flash back to the footprint of your childhood. Except, remember that bland vanilla ice cream between two chocolate wafers, the way the columns of chocolate stuck perfectly to your fingers? Those sandwiches will always have my heart, just as I’ll always love candy necklaces. But comparatively, Coolhaus’s skyscrapers are like Willy Wonka’s everlasting gobstoppers: architecturally interesting, edibly stimulating. And here we’ve hit on Coolhaus’ shtick (every trailer has to have one, after all). A riff on the name of the famed architect Rem Koolhaas and the influential Bauhaus movement, Coolhaus serves “architecturally inspired ice cream sandwiches.” Translation? A cookie roof and floor with ice cream walls, served to you from a 1985 vintage mall truck with green glass bricks on the roof.  The mini-chain started in L.A. in 2008 and now has outposts in New York and Austin. All of their offerings are made fresh with local ingredients, and their ice cream is hormone- and antibiotic-free. Plus, they serve their sammies in edible rice-paper wrappers. How tastefully green is that? Especially in the delirious Austin summer, you’ve got to admire Coolhaus’s philosophy: When it’s as hot as an oven out, bake cookies! Then use them to anchor lusciously cold ice cream. My favorite was the ever-popular double-chocolate cookie and Dirty Mint ice cream combo. It’s hard to beat just-baked, decadent cookies with the right amount of crunch and a huge scoop of thick, minty ice cream to cool you down. I also loved the mascarpone-and-fig ice cream: light and understated, with big hunks of juicy, balsamic fig. Though the soft, cinnamony snickerdoodle cookies were great, I was disappointed with Coolhaus’s recommended combination. Instead, I wish I’d tried the ginger cookies, which promised to be less bland. But there to save the day was the I.M. Pei-nut butter ice cream with chocolate chip cookies, bright and shining as the Louvre Pyramid, melodious as the notes echoing in the Morton H. Meyerson Symphony Center. What else can I say? This is my dream dessert, come to life. The peanut butter was rich and creamy, a perfectly smooth compliment to America’s favorite chewy-crunchy cookies. But if you’re looking for something less traditional, don’t despair: Depending on the day, the truck serves interesting offerings like lambrusco ice cream and oatmeal cookies with baked apple ice cream, not to mention gastro-experiments like brown-butter-with-candied-bacon ice cream. As much as I love standing by a trailer in the 104-degree heat with ice cream dripping down my arms, it is a bit ironic that Coolhaus’s architectural bent has not lent them a building with four walls and a blasting air-conditioning unit. But then again, they could just as well riff on old Corbu and say that food trailers are architecture, buildings are bourgeois. Two trucks: “Smokey,” 3600 Lamar, Thur & Fri 3–8, Sat 12–8. “Betty” roams; for hours and location, check their website and Twitter. Posted by Megan Giller. To read more from Megan Giller, visit her website at www.megangiller.com.