The burger: When Gather chef Josh Brown ran a bison burger special this past spring, it was an immediate hit, and quickly earned a place on the restaurant's menu.

With good reason. Naturally lean bison brims with a deep beef-like flavor, but it's not the world's juiciest meat. Which is why Brown wisely inserts a few fat boosters, namely a mixture of white onions slow-cooked in olive oil and jazzed by Dijon mustard and a splash of Worcestershire sauce. A side benefit is that the combination makes for an enticingly seasoned burger. And, yes, a relatively juicy burger.

This is one dense, tightly-packed patty. "That way they hold together really well," he said. For uniform portioning purposes, Brown relies upon an unorthodox form: the lid of an institutional-sized ketchup jar. "Yeah, it's the most expensive tool in the kitchen," he said with a laugh. "But it's a perfect size, because the patties cook down to the exact size of the bun."

For those considering a bison burger test-drive at home, Brown suggests using a cast iron skillet. "Instead of cooking it on a grill, we use a flat-top, so the patties cook in their own juices," he said. "That helps keep them nice and moist."

More juiciness comes courtesy of two key garnishes: a lemony aioli, and a gently fried egg. The latter really dials up the fat content that the bison lacks, especially as the runny yolk seeps into the patty. "Isn't everything better with a fried egg?" asked Brown with a laugh. Um, yeah.

Paprika-seasoned fried shallots contribute a crunchy texture element -- ditto the pert bread-and-butter refrigerator pickles -- and the whole smartly composed shebang is enveloped in a toasted, wonderfully chewy pretzel bun from the New French Bakery. Yeah, this one is definitely a keeper.

Price: $13, and available only at lunch.

The dining room sports one major freebie: an awesome big-city view, so be sure to ask for a window-side table. The vistas are even more impressive outside on the (really) sunny terrace. (For those interested in a pre- or post-lunch stroll through the Walker Art Center's galleries, admission is $12 for adults, $10 for seniors, $8 for students and free for children ages 18 and under. A tip: plan to visit on the first Saturday of the month, when admission is free. Admission to the Minneapolis Sculpture Garden is free.)

Fries: A $2 upcharge. Expect an enormous portion of long spuds fried to a deep amber and served with a decadent truffled aioli.

Outdoor extra: The distinctive plum-colored brick on the Walker's 1971 Edward Larrabee Barnes building is being replaced, a construction project that has prevented Brown from operating the terrific open-air patio grill near the museum's Vineland Place entrance. Instead, his outdoor crew is keeping busy this summer by manning a cute trailer parked in the Minneapolis Sculpture Garden, adjacent to an artist-designed mini-golf course.

It's called the Dog House. Expect to encounter Chicago-style hot dogs, along with the "Top Dog" (sauerkraut, fried onions and spicy mustard), the "Zen Dog" (vegetarian, topped with coleslaw), a kids' dog and, yes, the "Show Dog," a biweekly special ("It's where we get to play around," Brown said with a laugh) that currently piles on kimchi and a Sriracha creme fraiche; next up, Brown is planning an Italian-inspired formula of ham, Fontina cheese and marinara sauce.

The stand, which also hawks gelato, beer, soda and lemonade, is open 11 a.m. to 5 p.m. Sunday through Wednesday and 11 a.m. to 7 p.m.Thursday through Saturday.

Address book: 1750 Hennepin Av. S., Mpls., 612-253-3410.

Talk to me: Do you have a favorite hamburger? Share the details with me at rick.nelson@startribune.com.