Preheat and prep. Set your oven to 375°F (190°C). Grease a 9x9-inch (or similar) baking dish. If using frozen spinach, thaw it fully and squeeze out as much water as possible. If using fresh spinach, sauté it in a little butter until wilted, then drain.

Brown the beef. Heat a large skillet over medium-high. Add the ground beef and cook, breaking it up with a spatula, until no longer pink and lightly browned. Drain excess fat if needed, leaving about 1 tablespoon in the pan.

Sauté aromatics. Add the diced onion to the skillet and cook 3–4 minutes until softened. Stir in minced garlic and cook 30 seconds, just until fragrant.

Season well. Sprinkle in smoked paprika, oregano, thyme, onion powder, garlic powder, salt, and pepper. Stir to coat the beef and onions evenly.

Make the creamy base. Reduce heat to medium-low. Add butter and cream cheese to the skillet. Stir until the cream cheese melts and blends with the beef.

Pour in liquids. Add heavy cream and almond milk. Stir and let the mixture simmer 2–3 minutes, until slightly thickened and glossy.

Fold in spinach and cheese. Mix in the drained spinach, 1/2 cup mozzarella, and 1/4 cup Parmesan. Taste and adjust salt, pepper, or spices. If you like heat, add red pepper flakes.

Assemble. Transfer the mixture to the greased baking dish. Top evenly with the remaining 1/2 cup mozzarella and 1/4 cup Parmesan.

Bake. Place in the oven and bake 15–18 minutes, until the top is melted and bubbling at the edges.

Finish and serve. Let the casserole rest for 5 minutes so it sets slightly. Garnish with chopped parsley or chives. Serve warm.