CSRF Mismatch When POSTing from Ember to Sails Backend

First off, I just wanted to say that I have read through all of the other threads relating to this topic, but haven't had any luck. Here's a breakdown of the issue:

Goals

1. Retrieve a CSRF token from Sails when the Ember Application starts
2. Inject that CSRF token into every AJAX request that is initiated from the Ember Application

To satisfy goal 1, I created an Ember Initializer that runs when the application first boots up (if there is a better place for this, I'm totally open to suggestions). To satisfy goal 2, I retrieve the CSRF token from Sails and then attempt to use Ember.$.ajaxSetup() to ensure the CSRF token is passed either as a header or parameter (I've tried both and no success). I also ensure that I'm using the withCredentials option to ensure the cookie is set. Here's the code:

// initializers/csrf.js
import Ember from 'ember';
import config from '../config/environment';

export function initialize() {
  Ember.$.get(config.APP.API_URL + '/csrfToken').then(function(result) {
    Ember.$.ajaxSetup({
      data: {
        '_csrf': result._csrf
      },
      xhrFields: { withCredentials: true }
    });
  }, function(error) {
    console.log(error);
  });
}

export default {
  name: 'csrf',
  initialize: initialize
};

All of this appears to work as I can see in Chrome dev tools that the CSRF token is being retrieved and when I make an AJAX request, I see the data appended to the POST data. Here's the code I'm running and all of the associated headers:

Ember.$.post(config.APP.API_URL + '/auth/register', {
  'email': _this.get('email'),
  'password': _this.get('password')
}).then(function(response) {
  console.log('It worked!');
});

Request Headers

POST /auth/register HTTP/1.1
Host: localhost:1337
Connection: keep-alive
Content-Length: 82
Accept: */*
Origin: http://localhost:4200
CSP: active
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/43.0.2357.130 Safari/537.36
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
DNT: 1
Referer: http://localhost:4200/signup
Accept-Encoding: gzip, deflate
Accept-Language: en-US,en;q=0.8
Cookie: sails.sid=s%3AbrABhErTY3-ytTWOKFJ2KBj7DCAzaLDc.apD60Sd%2BW85GSbTfJ7E3B2PrUwnhOsW6GlNpZTu9jFg

Form Data

_csrf:yP7GDiU2-YGmLBfBvQtMPT3-hRpnfK0x-AfA
email:test@test.com
password:q1w2e3r4

Response Headers

HTTP/1.1 403 Forbidden
Vary: X-HTTP-Method-Override
Access-Control-Allow-Origin: http://localhost:4200
Access-Control-Allow-Credentials: true
Content-Type: text/html; charset=utf-8
Content-Length: 13
Date: Thu, 09 Jul 2015 08:11:34 GMT
Connection: keep-alive

As you can see from the Response headers, I end up receiving a 403 Forbidden - CSRF Mismatch from Sails. Now, here's where it gets a little weird: first, I'm able to run this just fine with Postman. I retrieve a token and then post that token along with the data to the /auth/register url and it works as expected.

I'm also tried removing the initializer and running the following code:

Ember.$.ajaxSetup({
  xhrFields: { withCredentials: true }
});

Ember.$.get(config.APP.API_URL + '/csrfToken').then(function(result) {
  Ember.$.post(config.APP.API_URL + '/auth/register', {
    'email': _this.get('email'),
    'password': _this.get('password'),
    '_csrf': result._csrf
  }).then(function(response) {
    console.log('It worked!');
  });
});

This works. However, at this point, I'm at somewhat of a loss as to what the issue actually is. Appreciate any help I can get.

Thanks in advance! James