gulp plugin looping through all files and folders

OK so I am creating a gulp plugin to create a table of contents and imports for my sass setup.

I have the gulp task all setup like this

var sgc = require('./tasks/sass-generate-contents');
gulp.task('sass-generate-contents', function(){
    gulp.src(config.tests + '/**/*.scss')
    .pipe(sgc(config.tests + '/_main.scss'));
});

and then my plugin code

function sassGenerateContents(){

    return through.obj(function(file, enc, cb){
        if (file.isNull()) {
            cb(null, file);
            return;
        }

        if (file.isStream()) {
            cb(new gutil.PluginError(PLUGIN_NAME, 'Streaming not supported'));
            return;
        }

        console.log(file);

    });

}

module.exports = sassGenerateContents;

in my file system (the test directory) are 3 x *.scss files

the console log in the plugin only ever returns the first. I'm probably missing somehting really obvious here, but I thought the idea of **/* was to loop through the folder structure specified and pull out the files.

Can someone explain to me why it's only returning the first file?

Thanks