I will be in Paris for a week in November; love the food but prefer not to eat big meals every evening. Are there restaurants more likely to offer a la carte menus? Can one order just a main course in a restaurant with a set menu of three courses? I'll be going to medium priced places, not the very expensive places. Thanks!

Every restaurant will allow you to order just one main course.

FYI

If you want an idea of what restaurant menus in Paris look like, just go to Google Maps and click on a restaurant name. You can find many photos of menus plus food, decor, exterior location, etc.

A brasserie will suit your needs.