JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.0/jquery.min.js"></script>

JavaScript

$.fn.meuAJAX = function(){
     var url = arguments[0];
     var dados = arguments[1];
     var callback = arguments[2];
    
     $.post(url,dados,callback);
  }

$(document).ready(function(){
  $(this).meuAJAX('/echo/json/',{data:'teste'},function(data){
    console.log(data)
  });
})