Short ribs with banana, nasturtium and black garlic. (Tim Carman/The Washington Post)

The eight-course preview dinner, clocking in at $119 per person (new slogan idea: “fine dining prices without the fuss”?), was held under what seemed like black tarps and spare hanging light bulbs. It felt simultaneously like an homage to Occupy D.C. and a M*A*S*H unit. I half wondered whether there might be incoming wounded.

As we were told upon seating, the concept’s name, Suna, is Latvian for “moss,” a nice nod to Spero’s Latvian grandmother. The food, however, strikes modern American (meaning essentially a cuisine that can borrow ideas from anywhere, right?) and even modernist notes, rather than anything smacking of the Baltic region. Which makes sense. Spero’s resume includes stints at Town House in Chilhowie, Va., Komi and even a stage at Noma in Copenhagen. Spero is a sponge, absorbing ideas wherever he wanders.

As a whole, Spero’s ideas haven’t yet fully formed into a coherent cuisine, at least that I could determine after a single meal. If anything, I’d say Spero is developing an Asian-influenced concept; a number of his small plates borrowed from East-leaning dishes (the Japanese influence on his chawanmushi), seasonings (the bold use of Japanese togarashi on the quenelle of sweet potato ice cream) and ingredients (the unmistakable use of Thai kaffir lime leaves in the short ribs).

“I just got back from Japan in January,” Spero, 26, tells me this afternoon. ”Maybe that’s why this menu was so focused on those flavors.” (He’s not expecting to turn Suna into an Asian-fusion restaurant, by the way.)

Not everything worked as I believe Spero had hoped. The Dungeness crab in a buttermilk emulsion (studded with freeze-dried grapefruit cells) would have fared better had the tartness of the fruit balanced out the sweetness of the crustacean meat. Similarly, the chawanmushi might have scored better with me had the mushroom variations (morels rehydrated with dashi, roasted maitakes and pickled bluefoots) pulled their weight with the savory, dashi-flavored custard and scallop dish.

I appreciate that Spero wants to give you different flavors with each bite, as he tried (unsuccessfully) with the chawanmushi but pulled off with greater aplomb with the opening course of kampachi “tartare.” Each bite of fish was accompanied by a different garnish: pickled radish, preserved lemon, rice gel, turning every mouthful into a new tasting experience.

My favorite plates of the evening were (to my considerable surprise) the mid-course meat dishes: The slices of cured and roasted duck were rendered nicely and paired with roasted/hay-smoked sunchokes, flowering herbs and a smoky stock steeped with those aforementioned kaffir lime leaves. It made for a stunning twist — the floral, citrusy leaves invigorated a tired fine-dining dish and suggested that Spero’s mind likes to wander outside standard-issue flavor combinations.

The chef’s short rib dish — paired with black garlic, nasturtium and banana — practically screamed DANGER AHEAD to me. I’ve had poor experiences with toques who want to combine sweet and savory flavors in hearty meat dishes. Spero’s version, however, was masterful; the slice of banana (cooked in a chili-spiked simple syrup) provided quiet background notes of sweetness, not unlike the caramelized sweetness of a rich, highly reduced stock (though I should add that the black garlic barely registered).

Desserts were, by and large, the weak spot of the evening. I found that the togarashi dominated the sweet potato ice cream, leaving an almost acrid taste in my mouth. (My tablemate for the night, I should add, loved the dish and didn’t find it out of balance.) The combo of hibiscus-steeped sorbet with black sesame crackers was essentially a flavor dud, brightened only when securing a bite of the basil garnish.

I should note that I visited Suna on its very first night as a pop-up; Spero tells me that small tweaks were made on subsequent evenings, which should give you an indication of his seriousness of purpose and his desire to keep pushing for better techniques and balance. I have high hopes for Suna when it officially opens as a brick-and-mortar restaurant this fall or early winter. Where you ask? Only Spero and his inner circle know.

“Technically we do have a space,” he says, “but we’re not releasing that [information] yet.”