Jose Andres, Carla Hall and Elizabeth Falkner are among the chefs who have signed onto a brief asking the Supreme Court to rule against a Colorado baker who refused to serve a gay couple.

The case, Masterpiece Cakeshop v. Colorado Civil Rights Commission, marks the first major case for the high court involving LGBT rights since Obergefell, the 2015 case that struck down same-sex marriage bans nationwide.

In 2012, Jack Phillips, the owner of Denver-based Masterpiece Cakeshop, refused to consider baking a cake for Dave Mullins and Charlie Craig. The men married in Massachusetts and wanted to buy a cake from Phillips for their Denver reception (Colorado at the time recognized gay and lesbian couples with civil unions, not marriage.). Phillips said that serving the couple would violate his religious faith.

The couple sued, saying that Phillips' faith does not give him a right to discriminate, and a Colorado court found that Phillips had discriminated against the men under Colorado law. After the Colorado Supreme Court declined to hear an appeal, Phillips turned to the Supreme Court, arguing that the First Amendment protects his religious rights.

(Related: Baker who refused gay couple says Jesus would do the same.)

In their brief, written by the Human Rights Campaign (HRC), the nation's largest LGBT rights advocate, the chefs deny Phillips' argument that anti-discrimination laws stifle a baker or chef's creative control.

“It's not about your art,” said Falkner, a celebrity chef who has owned restaurants in New York and San Francisco.

“I can decide what to create and what to serve, but not to say I won't serve it to a gay person, or a transgender person or a woman or a person of color,” said Mary Jennifer Russell, owner of Sugaree's Bakery in New Albany, Mississippi.

The U.S. Justice Department, under the leadership of Attorney General Jeff Sessions, has sided with Phillips, arguing in a 41-page amicus brief that “Forcing Phillips to create expression for and participate in a ceremony that violates his sincerely held religious beliefs invades his First Amendment rights.”