Preheat the oven to 375°F. Lightly grease a 9x13-inch baking dish (use additional olive oil).
Bring a large pot of salted water to a boil. Carefully add cauliflower florets and cook for 5 minutes. Rinse with cold water and drain thoroughly. Transfer to the baking dish.
Heat the olive oil in a large saucepan over medium heat. Add the onion and a pinch of salt. Saute 5 minutes, or until translucent. Add the garlic, first amount of thyme, and a pinch of salt and pepper. Saute 30 seconds, or until fragrant.
Stir in the soup, broth and ricotta cheese. Bring to a simmer, and cook for 5 minutes, stirring frequently. Season with salt and pepper. Remove from heat and pour evenly over cauliflower. Cover with foil, and bake for 35 minutes.
In a small bowl, mix together the shredded Parmesan cheese, second amount of thyme, and gluten-free crackers or bread crumbs, if using.
Carefully remove the foil, and sprinkle Parmesan mixture evenly over the surface. Bake, uncovered, for an additional 10 minutes, or until the topping is golden.
Remove from the oven, and set aside to cool slightly. Serve, and enjoy!
This nutritional information refers to each serving of the entire recipe and not just the products used as ingredients.