Firstly, preheat oven to 400° F (200° C). Grease a 3-quart casserole dish and set aside.
In a small bowl, mix the breadcrumbs, melted butter, and a dash of garlic powder. Set aside.
To soak cashews, boil water in a small pot and remove from heat. Add cashews and cover for 15-20 minutes, until softened.
After that, you can steam the cauliflower while the cashews are soaking. In a large saucepan that will accommodate your steamer basket. Add approximately 1" of water. Put your basket on the bottom, and then put a lid on the pot. Turn up the heat and bring to a boil. Once boiling, reduce heat to medium-low to maintain a gentle boil. Then add cauliflower florets to the basket. Cover and steam for 7-10 minutes, until tender. Uncover and remove from heat.
Rinse and drain the cashews (discard soaking water). Now combine all the ingredients for the cheese sauce in a powerful blender. After around 1-2 minutes of blending, time will get the sauce smooth and the cashews are broken down.
Over medium heat, add cheese sauce to a medium skillet or pot (I used the same pot for steaming the cauliflower). Sauté for 4-5 minutes, or until it thickens and starts to stretch a bit. To avoid burning, stir it in a frequent way. You can thin out the sauce if it is too thick for your taste by adding more soy milk or broth. If more seasoning is required, taste the food first.
In addition, fill the bottom of the casserole dish with grease and then add half the cheese sauce. At this point, stack the cauliflower on top. On top of the cauliflower, drizzle the leftover cheese sauce. In the following step, top with foil and sprinkle with prepared breadcrumbs. The cheese should be hot and bubbling after 15 to 20 minutes in the oven. When the breadcrumbs are golden brown and the foil is removed, bake for 10 more minutes. Remove from the oven.
Lastly, sprinkle red pepper flakes and fresh, chopped parsley, if desired. Enjoy!