gulpSassFunction.js

// Convert sass to css
gulp.task('sass', function(){
  return gulp.src('sass/**/*.scss') // this globs all .scss files found in folder/subfolders
    // Initializes sourcemaps
    .pipe(sourcemaps.init()) // this produces a sourcemaps at the bottom of our .css file for browser debugging
    .pipe(sass({
      errLogToConsole: true // this will log sass console errors in the terminal
     }))
    // Writes sourcemaps into the CSS file
    .pipe(sourcemaps.write())
    .pipe(gulp.dest('css'))
    .pipe(browserSync.reload({
      stream: true // this will reload browserync everytime we modify a .scss file
    }))
});