Finally, two blossoms opened up yesterday and I was able to hand-pollinate (I'm way too curious to trust the bees on this one!). It's growing already! I know it kind of looks like zucchini, but the color is too light. I suppose it could be a variety I've never grown before, but I still think it's something else. Anyone think it could be delicata? That's what I'm hoping for!
Next mystery plant update will be after I get back from vacation and I think by then we should know for sure!