package.json
dist/
Gruntfile.js
src/
  partials/
    partial.handlebars
  views/
    thing1.handlebars
    thing1.json
    thing2.handlebars
    thing2.json

module.exports = function(grunt) {

  grunt.initConfig({
    jshint: {
      files: ['Gruntfile.js', 'src/**/*.js', 'test/**/*.js'],
      options: {
        globals: {
          jQuery: true
        }
      }
    },
    watch: {
      files: ['./src/*', './static/*'],
      tasks: ['compile-handlebars']
    },
    'compile-handlebars': {
      compileRootTemplates: {
        files: [{
            expand: true,
            cwd: './src/views/',
            src: '*.handlebars',
            dest: './dist/',
            ext: '.html'
        }],
        templateData: './src/views/*.json',
        partials: './src/partials/*.handlebars'
      },
  });

  grunt.loadNpmTasks('grunt-compile-handlebars');
  grunt.loadNpmTasks('grunt-contrib-watch');

  grunt.registerTask('default', ['compile-handlebars']);

};

...
'compile-handlebars': {
      compileRootTemplates: {
        files: [{
            expand: true,
            cwd: './src/templates/',
            src: '*.handlebars',
            dest: './dist/',
            ext: '.html'
        }],
        templateData: './src/data/*.json',
        partials: './src/partials/*.handlebars'
      },
  });
...