Preheat your oven to 375°F (190°C). In a small bowl, combine crushed pork rinds with half of the shredded Gruyère and grated Parmesan, and set aside.

In a skillet, heat olive oil over medium heat. Add leeks and sauté for about 3-4 minutes. Stir in garlic and thyme, cooking for another 45 seconds.

Incorporate the well-drained spinach into the skillet. Stir for 2-3 minutes until heated through.

Reduce heat to low, add mascarpone, heavy cream, salt, black pepper, and nutmeg. Stir until smooth.

Remove from heat and fold in the remaining Gruyère and Parmesan until melted.

Spread the spinach mixture in a baking dish and sprinkle the topping over it. Bake for 20-25 minutes.

Switch oven to broil for 1-2 minutes until the top is crispy. Let rest for 5 minutes before serving.