JSFiddle - React, Tailwind, and code Playground

HTML

<label>Search:</label>
<form name="findrecipe" action="#">
    <input type="radio" name="search" id="search_name" value="name" checked />Name
    <input type="radio" name="search" id="search_ing" value="ingredients" />Ingredients<br/>
    <input class="searchbox" type="text" name="searchBox" />
    <br/>
    <input type="submit" value="Submit" />
</form>

JavaScript

$(function() {
    $('form').on('change', '.searchbox', function() {
       $('form').append('<br/><input class="searchbox" type="text" name="searchBox" />');
    });
});