How do you pass parameter to gradle from jenkins job dsl?

Question

I have a job where I can pass in command line arguments like

gradle -Pconf=prod build

How do I pass arguments in jobs dsl?

I tried the following but it doesn't work

job("doSomething"){
    steps {
       gradle('-Pconf=prod build')
    }
}
job("doSomething"){
    steps {
       gradle('build', '-Pconf=prod')
    }
}
job("doSomething"){
    steps {
        gradle{
        tasks('build')
        tasks('-Pconf=prod')
       }
    }
}
job("doSomething"){
    steps {
        gradle{
        tasks('build')
        switches('-Pconf=prod')
       }
    }
}

job dsl plugin version 1.48