Wash the fresh spinach thoroughly, then blanch it in boiling water for 1-2 minutes until wilted. Drain the spinach well and squeeze out any excess water using a clean kitchen towel or paper towels.

Chop the blanched and drained spinach finely, ensuring there are no large chunks. In a large bowl, combine the chopped spinach with the ricotta cheese, grated Parmesan cheese, and the large egg.

Season the mixture with nutmeg, salt, and black pepper, then mix all ingredients thoroughly until well combined. Before proceeding, taste and adjust the seasoning as needed to your preference.

Heat olive oil in a large non-stick skillet or oven-safe dish over medium heat. Once hot, carefully add the spinach and ricotta mixture to the skillet, spreading it evenly.

Cook for 15-20 minutes, stirring occasionally, until the mixture is heated through and slightly golden on the bottom. Alternatively, you can bake it in a preheated oven at 375°F (190°C) for 20-25 minutes until bubbly and lightly browned.