My wife and I spent a day and night in Chartres recently. We ate extremely well at Restaurant le Saint Hilaire, a farm-to-table restaurant on the river. We enjoyed pan fried prawns, sea bream, risotto with cockles, seared scallops, and roasted lobster. The next day at lunch we ate at Cafe Bleu (http://www.cafebleu-chartres.com/), a classic bistro with delicious egg dishes as well as well-prepared fish and pork.
I know Chowhound is about food, but I have to say that the real find of our trip, however, was the place we stayed. Le Jardin Cathedrale (https://www.lejardincathedralechartre...) is a beautifully furnished and maintained 18th century house only 3 blocks from the cathedral. You enter from the street through a door in a plain wall -- the only sign that it is a hotel is the sign above the door bell. Ring that bell and the owners welcome you into what is truly another world, a magical world, a house that wraps around a large garden where the spires of Chartres Cathedral rise above the garden wall. The owners rent two rooms, both of which are elegantly furnished. The whole place is elegantly furnished, and shows years of devoted care.
To get this back to food, however, the breakfasts are delicious. Hot coffee, elegant pastries, delicious jams, the best of French butter. And all this for only about 100 euros a night.