Emberfire belongsTo and findAll

Question

I have two models:

models/cake.js

export default Model.extend({
  name: attr('string'),
  factory: belongsTo('factory', { inverse: 'cake', async: true }),
});

models/factory.js

export default Model.extend({
  name: attr('string'),
  cake: hasMany('cake', { inverse: 'factory' }),
});

And I trying in my router:

model() {
  this.store.findAll('cake');
}

But the {{model.factory}} is empty

Why?