Of course, it would be nice to have the answer to that before you buy advance tickets for the eight- to 12-course meal at $155 a person, the only way to reserve a seat. But it doesn’t take more than a few minutes at Gem to see that the adults weren’t just humoring Mr. McGarry. His cooking is nuanced, his plating is often lyrical and the flavors, at least this spring and summer, have been delicate, subtle and very fresh. The vegetables and fruits he uses in profusion look and taste as if they had dropped off the vine right on to the hand-spun, earth-toned ceramic dishes.

My favorite Gem dish so far, delicate and self-assured, was a morsel or two of grilled king crab legs lightly glazed with rose petal miso and set beside soft chamomile-scented potatoes for ballast, red currants for zing and some fluttering rose petals on top for the heck of it. A close rival was the chilled bowl of barely vinegared mackerel interwoven with grilled cucumbers, sliced plums and salty red dabs of mashed fermented plums. The harmonies were right on key, with a Japanese mood that didn’t cross the line into outright imitation.

White asparagus, an ingredient that seems to flummox some American kitchens, was subjected to a wonderful treatment, patiently browned and basted in butter, then finished with a reduced chicken jus that had a glimmer of vadouvan in it somewhere. Strewing the plate with tender, pale-green pine needles seemed like an affectation at first, but their flavor lifted and brightened the whole package.

Mr. McGarry does fine work with deeper flavors, too. Each menu crescendos in a complicated, multicomponent spread, and the best of these featured lamb: barbecue ribs rubbed with cracked coriander seeds and XO sauce, plus a skewered grilled lamb kebab and a tomato salad. Another night built up to an exhibition of squab. A leg, perfectly cooked and sweetened by a maple jus, was very good, but the high point was a very thin and hearty rye cracker spread with squab liver, cherries and pickled ramps; the fruit’s bright notes were played off against earthier ones so skillfully they almost shimmered.

Back in the family home, and at the Eureka pop-up, Mr. McGarry used to make everything himself. Now he works alongside two cooks, bringing the kitchen team at Gem to the same size as that of my neighborhood slice joint.