Place a rack in the center of the oven and preheat the oven to 325. Lightly mist a 13x9 inch glass or ceramic backing dish with vegetable oil spray and set the dish aside.
Place the broccoli in a large microwave-safe glass bowl and microwave on high power until thawed--about 1 1/2 to 2 minutes. Leave the broccoli in the bowl and drain it over the sink pressing on it with a fork to extract as much liquid as possible.
Add the butter, eggs, ricotta, 1 cup of the Cheddar cheese, and the flour, salt and hot pepper sauce. Taste for seasonings, adding black pepper to taste and more salt abd/or hot pepper sauce as desired. Stir to combine well. Transfer the broccoli mixture to the baking dish and scatter the remaining Cheddar cheese evenly over the top.
Bake the casserole until it turns golden brown and bubbles around the edges, 48 to 52 minutes. Let the casserole cool for at least 10 minutes before cutting it into squares to serve.