Heat vegetable oil in a sauce pot, add ground beef and season with salt and pepper. Brown for 5-8 minutes.
Add onions, garlic and Italian seasoning to the pot, stir to combine and cook til onions are soft and translucent. 5-8 minutes
In a large mixing bowl toss all the florets with olive oil, salt and pepper.
Add the florets to a deep 13x9 baking dish and cover with tin foil. Pierce the tin foil and bake for 20 minutes
While the florets bake, combine the spinach, ricotta, parmesan and about 1/3 of the mozzarella
When the florets are done, remove them from the oven and discard the foil. Layer the meat sauce into the dish, followed by the spinach and cheese, followed by the remainder of the mozzarella.
Bake for 40 minutes at 350F. Rest for 10 minutes and serve.