Preferably also gluten-free.
Well, I don't know how much you care about seasonality, but ratatouille can easily be made as a vegan offering.
There are enough ratatouille recipes on this planet to fill up the Library of Congress. Pick one from a reputable source and sub water/vegetable stock for any meat stock. Most recipes will not have any gluten ingredients anyhow, it's just vegetable stew.
Smitten Kitchen's mushroom bourguignon can easily be made vegan and gluten free (use vegan margarine for the butter or just double the olive oil, and use a gluten free thickener like arrowroot powder.). I like to add a bit of fresh rosemary in addition to the fresh thyme. http://smittenkitchen.com...
I second the Smitten Kitchen mushroom Houghton idea. If it really needs to be vegan (and not just vegetarian) coconut oil or just more olive oil works. You can use tapioca starch or flour to thicken (or a cornstarch slurry for that matter) and it's delicious over mashed potatoes if you want to skip the noodles.
Houghton? Supposed to read bourguignon.
Wintery, vegan and gluten-free: try this!
In addition to the good ideas so far, consider this mixture of roasted quinces and root vegetables. Unusual, savory and winter seasonal.
You can also glean lovely vegan stews from both Anna Thomas and Mollie Katzen. They have recipes online.
Gosh...some great ideas here. Thank you, all.