Preheat the oven to 375F (190C).

Heat the olive oil in a large skillet over medium-high heat. Add the ground beef and cook for 6 to 8 minutes, breaking it up as it browns, until no pink remains. Drain off the excess fat.

Stir in the onion powder, paprika and the thawed, well-squeezed spinach. Cook for 2 minutes, stirring, until any remaining moisture has cooked off.

Turn the heat down to medium-low. Add the cream cheese and heavy cream and stir until the cream cheese has melted into a smooth sauce, about 3 minutes. Stir in the Parmesan until melted.

Taste, and season with salt and black pepper as needed.

Transfer the mixture to a 1.5 to 2-quart baking dish and spread it level. Bake uncovered for 15 to 20 minutes, until bubbling and golden brown on top.

Let the casserole rest for 5 minutes before serving.