Preheat the oven to 180°C (356°F).

Cook 250 grams of pasta shells according to the package instructions until al dente, then drain and set aside.

In a large skillet, melt 2 tablespoons of butter over medium heat. Add 2 minced garlic cloves and sauté until fragrant, about 1 minute.

Add 200 grams of fresh spinach to the skillet and cook until wilted. Stir in 1 teaspoon of dried marjoram, a pinch of nutmeg, and 2 tablespoons of chopped basil, cooking for another minute.

In a mixing bowl, combine the cooked spinach mixture, 100 grams of ricotta, 100 grams of grated mozzarella, 50 grams of marzipan (finely chopped), 2 tablespoons of crème fraîche, and 1 tablespoon of sugar. Mix until well combined.

Fill each cooked pasta shell with the spinach and cheese mixture and arrange in a baking dish.

Bake in the preheated oven for 20 minutes, or until the tops are lightly browned and the filling is bubbly.

Serve hot, garnished with additional basil if desired.