A green rock counter curves in front of bulbous plaster walls inside this bar in Williamsburg, Brooklyn, designed by local architecture studio Isaac-Rae for a space tucked behind a cafe.

Isaac-Rae – run by husband and wife Clay and Margot Coffey – completed cafe-cum-cocktail spot Bar Beau for a slender space at 61 Withers Street.

The front portion is occupied by a coffee and pastry shop that operates during the day, while the rear cocktail bar – which also serves small plates – opens at night.

Isaac-Rae chose a simple and rustic material palette, and curvaceous forms to reference Bar Beau owner Claire Chan's home in North America's Pacific Northwest region.

Textured grey floors and stained black ceiling beams feature throughout. Walls are a mix of white-painted brickwork walls and curved plasterwork, and form a narrow meandering passageway from cafe to bar.

"[The] design draws upon the rough edges, waves, and natural palette of the wild coastline of the Pacific Northwest," said the studio in a project statement. "We focused on creating a space with atmosphere that was fluid like the coast: calming to be in, easy to move within."

Behind the bar counter, a protruding section of the back wall has a large section cut out to create a cabinet for storing drinks.

The green leathered quartzite bar in front ends in a curve at one end. A chunk on top features tapered edges, while the underside has an angular profile.

Seating is provided by black bar stools around the counter and dark wooden benches built along the walls. Another seating nook is built into the far corner.

One the other side of the room, a pink neon light illuminates an arched doorway to the bathroom. An adjacent arch-shaped window also provides a view to the kitchen.

Curving forms continue the in coffee shop, where the rounded counter for serving customers is faced in wood. A series of latticed pink-hued pendant lamps hang from the ceiling, and a slender counter with bar stools runs along one wall for customers to enjoy their drinks.

These muted tones form a stark contrast to Bar Beau's bright blue front, which helps it to stand out on the bustling Williamsburg street.

In neighbouring Greenpoint, architect Arnold Cheung created a similar hybrid bar and restaurant – with a ramen shop at the front and a tiny Japanese-style speakeasy tucked in the back.

Over in Manhattan, a cafe called Patent similarly provides a front for an after-hours speakeasy.

Photography is by Isaac-Rae.