How to add a contact form widget?

Is there a way to add a form as a widget? Eg. in sidebar or after a blog list or where ever my theme includes the form template. I started by checking this widget recipe, but it’s so simple and I still have no idea where to put blueprints for the form or if I have to create some invisible page to submit form to. I’d prefer this would be an AJAX form. Checked this AJAX form tutorial, but it seems as a separate page and not a widget, which I could include in any template.

Any advice?
Grav 1.7 RC2

Thank you