build DOM elements with a helper

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle'
});

helpers.build-dom-node.js

import Ember from 'ember';

export function buildDomNode(params/*, hash*/) {
  const text = params[0];
  const div = document.createElement('DIV');
  div.style.backgroundColor = '#0000ff';
  div.style.color = '#fff';
  div.innerText = text;
  return div;
}

export default Ember.Helper.helper(buildDomNode);

templates.application.hbs

{{build-dom-node "hello world"}}
{{log (build-dom-node "hello world")}}

twiddle.json

{
  "version": "0.12.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.12.0",
    "ember-template-compiler": "2.12.0",
    "ember-testing": "2.12.0"
  },
  "addons": {
  }
}