The patties should hold together without adding an egg, but if the mixture is very warm or the ingredients aren’t measured exactly, they can sometimes be softer than expected. Chilling the patties before cooking helps them firm up, though results can vary depending on factors like the fat content of the beef used.

An egg can certainly be added if you prefer a firmer texture.

Yes, most of the alcohol in the bourbon cooks off during the cooking process, especially since the sauce simmers for several minutes. The bourbon is mainly used to add flavor and depth to the sauce. That said, it’s difficult to say that every trace of alcohol is completely gone. If you prefer, you can also substitute apple juice, chicken broth, or even water for the bourbon and still have a delicious sauce.

The way the recipe is written, you need to use cooked chicken. You can pre-cook chicken and shred it or shred a rotisserie chicken in place of canned chicken.