I often do this with a bagel. I add some sweetcorn relish or caramelized onion relish as well as hummus to add flavor. You can also do this with vegetable sausages; slice them up and then make a sausage sandwich.
Is that your own recipe or store bought?? I'm on a mission to make the perfect burger for my kids. We've gone through a few and we have some faves, but obviously nothing beats cow when you're not a willing vegan lol. Recipe?