Sweet Potato Casserole

Ingredients:

Casserole

• 1.3 kg sweet potatoes (about 3 large tubers)
• 2 x 280g packages frozen chopped spinach, thawed
• 450 gr. mozzarella, grated
• 900 g ricotta
• 0.5 tbsp. grated parmesan
• 1/4 tsp. grated nutmeg
• 2 large eggs, lightly beaten

Tomato sauce

• 3 tbsp. l. olive oil
• 1 small onion, chopped
• 2 cloves garlic, crushed
• 1 can (800 g) of canned whole peeled tomatoes

Preparation:

1. Tomato sauce:
   
   Heat the olive oil in a medium saucepan over medium heat. Add the onion and 1/2 teaspoon salt and cook, stirring frequently, until softened and translucent, about 10 minutes. Add the garlic and cook for 2 minutes. Add the tomatoes and mash with a potato masher until chunky. Bring to a simmer and partially cover the pan. Simmer, stirring occasionally, until the sauce thickens slightly, about 30 minutes. Stir in 1/2 teaspoon salt and season with pepper to taste. Remove from heat.
2. Casserole:
   
   While the sauce is simmering, drain the spinach, place it in a clean kitchen towel, and squeeze well to remove excess water. Place the spinach in a large bowl. Set aside 1 cup of the saucepan. Then, add the remaining mozzarella to the bowl with the spinach. Add the ricotta, Parmesan, nutmeg, eggs, 2 teaspoons of salt, and 1/2 teaspoon of black pepper. Stir with a wooden spoon or silicone spatula to evenly distribute the ingredients.
   
   Peel the sweet potatoes and trim a little off one of the longer sides of each potato to ensure they stand up straight and don't roll. Slice the sweet potatoes lengthwise into 0.5 cm thick slices.
3. Preheat oven to 175°C.
4. Assembly:
   
   Spread about 3/4 cup of sauce in the bottom of a deep 9 x 13-inch baking dish. Arrange a single layer of sweet potato slices along the bottom. Top with one-quarter of the ricotta-spinach mixture and, using a spatula or the back of a spoon, gently spread it into an even layer. Spread about 3/4 cup of sauce on top. Then arrange another layer of sweet potato slices, facing away from the previous layer. Repeat with the ricotta mixture and sauce until you have 4 layers, finishing with the remaining sauce.
5. Cover the pan with foil and bake for 25 minutes. Remove the foil, sprinkle with the remaining mozzarella, and bake until the casserole is bubbly, the mozzarella is crisp, and the sweet potato is tender when pierced with a knife, another 45 to 60 minutes. Let rest for 20 minutes, then slice and serve.