This one just kind of emerged out of an extra egg white, extra tequila (the best kind), and a random syrup hanging about in the fridge. Turned out pretty dang well.
2 oz reposado tequila
3/4 oz brown sugar-butternut squash syrup
1/4 oz orange curacao
1 oz lime juice
1/2 egg white (good luck dividing that; you'll just have to make two)
Combine and shake without ice, then add ice and shake again. Strain into a rocks glass over a couple of extra cubes. Do not even consider garnishing, unless it's with a little bit of grated nutmeg and lime peel. Which it should be.
Frankly, I would have loved to try this with mezcal and a couple dashes of chocolate bitters... but you do what you can with what you have.