Lightly oil (or spray with a light mist of oil) a large casserole dish and set aside. Place the cauliflower florets in a steamer basket and steam for 5 to 6 minutes or until crisp tender. Transfer the cauliflower florets to the prepared pan and set aside. In a saucepan, whisk together the oil and flour until it forms a smooth paste. Whisk in the soy milk and cook the mixture over low heat, while whisking constantly until thickened, about 2 to 3 minutes. Remove the saucepan from the heat. Whisk in the tofu sour cream, parsley, dill, yeast flakes, salt, pepper, and nutmeg. Pour the mixture over the cauliflower, then sprinkle the breadcrumbs over the sauce, and generously sprinkle the Hungarian paprika over the top of the breadcrumbs. Bake at 375 degrees F for 20 to 25 minutes or until the sauce is bubbly and the top of the casserole is golden brown.