Tian is the Provençal name for gratin, which is usually a vegetable dish but occasionally includes meat. This tian is as Provençal as the lavender that blooms in summer and the gray-green olive trees that dot the hills of the region. Traditionally made with the small purple artichokes of Provence called poivrades, it is also flavorful made with the more common, larger artichokes. The combination of vegetables--softened with a bit of cheese--is irresistible.
Heat a large nonstick skillet over medium heat. Add the spinach in batches, turning frequently until wilted (about 7 minutes). Drain spinach (it should be neither wet nor dry, but moist). Combine spinach and garlic in a medium bowl.
Combine water and lemon juice. Working with 1 artichoke at a time, cut off stem to within 1 inch of base; peel stem. Remove the bottom leaves and tough outer leaves, leaving the tender heart and bottom. Cut artichoke in half lengthwise. Remove fuzzy thistle from bottom with a spoon. Thinly slice artichoke heart; place in lemon water. Repeat procedure with remaining artichokes. Drain. (You should have about 4 cups sliced artichokes.) Sprinkle artichokes with salt and pepper.
Preheat oven to 375°.
Arrange 3 cups artichoke in an 11 x 7-inch baking dish coated with cooking spray. Sprinkle with 1/2 cup cheese. Repeat layers with artichoke and spinach.
Cover and bake at 375° for 15 minutes. Uncover and bake 30 minutes. Sprinkle with 3/4 cup cheese. Bake an additional 10 minutes or until artichokes are tender.