Queueing emails with Python, Redis Queue, and Twilio SendGrid is a useful technique for asynchronously sending emails from within a web application without blocking requests. By using the `requests` library to make an HTTP request to the Taco Fancy API, which returns a randomly generated taco recipe in markdown format, we can convert this data into HTML content using the `markdown2` library and then send it via Twilio SendGrid. To improve efficiency, we use Redis Queue to enqueue jobs for each email that needs to be sent, allowing us to take advantage of asynchronous processing without blocking requests. This approach enables developers to generate and send emails without waiting for previous requests to complete, making it a valuable technique in web development.