Preheat your oven to 425°F (220°C) to ensure it's ready for baking your Easy Christmas Stuffed Shells.

Steam your spinach on high heat for about 1 minute until wilted, then chop finely and squeeze out excess moisture.

Bring a large pot of salted water to a boil, add pasta shells, and cook for approximately 10 minutes until al dente. Drain and drizzle with olive oil.

In a mixing bowl, combine chopped spinach, ricotta, pecorino, garlic, oregano, lemon zest, and red pepper flakes. Mix until well blended.

Spread marinara sauce across the bottom of a 9×13-inch baking dish.

Stuff each shell with the spinach and cheese mixture and arrange in the baking dish over the marinara sauce.

Cover the baking dish with aluminum foil and bake for 20 minutes.

Remove the foil, let cool for a few minutes, and serve hot, optionally drizzling with extra marinara sauce.