Trying to instantiate a bean with the CDI from a running webapplication

I have a jar that contains a @Stateless class defined like

 @Stateless 
 public class TestBean() {
     @Inject 
     AnotherBean bean2;
     public String getThis() {
      return bean2.getAString();   
     }
 }

A webapplication (with a dependency on this jar) running on wildfly 10.1.0 would like to instantiate this bean and use its methods. The webapplication calling method might be a rest endpoint (called by some other webapplication) or just a regular java method.

What is the best way to instantiate TestBean? I have tried several solutions none of which works.

For example this one

Building a CDI 2 standalone

and this one

Does CDI work for regular Java application?

I am new to the CDI and how it works, I am wondering if this is explained well somewhere?