Preheat your oven to 375 F. This ensures your Baked Penne bakes evenly and develops a lovely golden crust.
In a large pot, bring salted water to a full boil. Add the Penne Rigate Pasta and cook according to the package instructions until it’s al dente, which means it should be firm to the bite.
Once cooked, drain the pasta and return it to the pot. Pour in the Tomato Sauce and mix well until the pasta is coated.
Next, add all but one cup of the prepared bechamel sauce to the pasta and stir to combine. This will create a rich, creamy texture.
In a separate bowl, mix in the Parmigiano Reggiano and three quarters of the Mozzarella into the pasta mixture, ensuring it’s evenly distributed.
Pour the remaining cup of bechamel into the bottom of an ovenproof baking dish. This layer prevents the pasta from sticking and adds moisture.
Now pour the pasta mixture into the baking dish, smoothing the top with a spatula. This ensures even cooking.
Sprinkle the top with the remaining Parmigiano Reggiano and Mozzarella to create a cheesy crust.
Dot the top with the remaining two tablespoons of Unsalted Butter, cutting it into small pieces. This adds richness and flavor.
Place your baking dish in the preheated oven and bake for about 20 minutes, or until the top is bubbly and golden. If you prefer a crispier top, broil for a couple of minutes at the end.
While the pasta is baking, melt the Butter in a large, heavy-bottomed pan over medium heat. Whisk in the Flour until a thick cream forms. This is the start of your creamy bechamel sauce!
Slowly add the Whole Milk, whisking continuously to avoid lumps. Keep stirring until the sauce thickens and coats the back of a spoon.
Season the sauce with Salt, Pepper, and a pinch of Nutmeg for a warm flavor. Once ready, remove it from the heat.