Prep:

1. Prepare the fresh and canned ingredients: Chop the yellow onion, garlic, fresh red chilies, and Italian parsley as indicated in the ‘ingredients’ section. Wash the baby spinach. Drain the canned corn and tuna into separate fine mesh strainers.
2. Combine the spices and seasonings: In a small bowl, combine the kosher salt, freshly cracked black pepper, garlic powder, onion powder, Herbs de Provence, dried oregano flakes, ground cayenne, and crushed red pepper flakes. Cover and set aside.
3. Grate the cheeses: Grate the mozzarella, Gruyère, and Parmigiano Reggiano cheeses using a box grater. Set aside half of each type of cheese (1 cup mozzarella, ½ cup Gruyere, and ¼ cup Parmigiano Reggiano cheese) for the cheesy topping. Combine the remaining cheeses for the creamy pasta sauce in a large measuring cup or bowl.

For the Creamy Tuna Pasta Bake:

1. Cook the pasta: Cook the pasta in a large pot (or use the same pan you’ll use to make the sauce) of boiling salted water 2 minutes shy of the time stated on the package for al-dente pasta. Drain and run cold water over the pasta to halt the cooking process.
2. Preheat oven: Preheat over to 350°F/180°C.
3. Sauté onion and aromatics: Heat the unsalted butter and extra virgin olive oil in a large deep sauté pan over medium-high heat. Once the butter is frothing, add the yellow onion and garlic. Sauté for a minute until slightly softened. Add the fresh red chilies (if using) and parsley and sauté for another 30-40 seconds until fragrant.
4. Add the flour and wine: Whisk in the all-purpose flour and cook for 1-2 minutes until combined well. Gradually pour in the dry white wine and continue whisking to combine. The wine will reduce and the mixture will thicken.
5. Build the cream sauce: Lower the heat to medium and add 1 cup of milk. Whisk until smooth and thickened. Then gradually pour in the remaining milk while continuing to whisk. Stir in all of the spices and seasonings and continue whisking until combined well and the sauce has thickened – about 3-4 minutes.
6. Stir in the cheeses: Stir in the mozzarella (1 cup), Gruyere (1/2 cup), and Parmigiano Reggiano (1/4 cup), one handful at a time and making sure each addition has fully melted and integrated before adding the next handful. Remove the pan from the heat.
7. Add the veggies: Add the corn and baby spinach. Stir until the baby spinach has slightly wilted.
8. Add the lemon juice, pasta and tuna: Gently stir in the lemon juice, pasta, and tuna until combined well, taking care to not break the tuna chunks too much so that it turns into mush.
9. Bake and broil: Transfer to a 9×13-inch baking dish. Sprinkle the reserved mozzarella, Gruyère, and Parmigiano Reggiano cheeses evenly on top. Bake for 20-22 minutes until the cheese has melted. Then broil for 2 minutes until the cheesy topping is golden brown and bubbling at the sides. Transfer the dish to a wire cooling rack and allow to cool for 5-10 minutes.
10. To Serve: Garnish with chopped parsley if desired and serve immediately.