Grownup Tuna Noodle Casserole

This beloved (or thwarted, depending on your history) household staple receives a major upgrade. Between this recipe’s deeply savory flavors thanks to dijon mustard and capers, the sweet butteriness the delicata adds, and subtle tangy creamy sauce - punctuated by the crispy topping - this take on tuna noodle casserole elicits rousing applause. It’s a perfect deep winter snow-day project, and warms on the inside and out.

Grownup Tuna Noodle Casserole

Serves 6

INGREDIENTS

• Unsalted butter, for greasing the pan

• Extra-virgin olive oil, for sautéing

• 2 delicata squash, halved crosswise, seeded, cut into ⅛- to ¼-inch rings

• Kosher salt, to taste

• 1 large yellow onion, finely chopped

• 8 oz cremini mushrooms, sliced

• 2 tbsp capers, chopped

• 2 garlic cloves, finely grated on a Microplane

• ¼ cup dry white wine

• 2 tbsp Dijon mustard

• 3 tbsp all-purpose flour

• 2 cups chicken or vegetable stock

• Freshly ground pepper, to taste

• 1 cup heavy cream

• ½ cup buttermilk

• 3 oz Parmesan cheese, finely grated, divided

• 7 oz shell pasta

• 2 (6-ounce) cans oil-packed tuna, drained, coarsely shredded

• ½ cup panko

• ¼ tsp freshly ground black pepper

• ⅓ cup dill sprigs

DIRECTIONS

1.  Grease a 9x13-inch casserole dish and heat the oven to 400°F. Set a large pot of water over high heat to come to a boil. 

2. Add 1 tablespoon of oil to a large cast-iron skillet over medium heat. Add enough delicata to fit in a single layer and season with salt. Cook for 4 to 5 minutes, until soft and caramelized in places. Flip the rings and sauté for another 3 to 4 minutes, until browned. Transfer cooked rings to a large plate and repeat with the remaining squash. Once all the squash is cooked, arrange the thicker slices (just over half the squash) as a base layer in the casserole dish.

3. Add another tablespoon of oil and swirl to coat the pan. Sauté the onion for about 7 minutes, until translucent, stirring occasionally. 

4. Add the mushrooms and season with salt, plus a small drizzle of oil if the pan looks dry. Stir to combine and sauté for 5 to 7 minutes, until mushrooms give up their liquid and become tender. 

5. Add the capers and garlic and sauté until the garlic is fragrant, about 3 minutes.

6. Add the wine and cook it away almost completely, about 3 minutes. 

7. Stir in the mustard, then the flour. Cook for 1 minute over medium heat (it will be clumpy—that’s okay), constantly stirring. Stir in the stock and season with black pepper. Stirring constantly, bring it to a boil, then keep stirring and cooking until the liquid has thickened slightly, about 5 minutes. 

8. Stir in the cream, then bring back to a boil. Stir in the buttermilk, then remove the pan from the heat. Stir in ⅔ of the Parmesan. Pour half of the sauce into a heatproof bowl and fold in the tuna. Taste and adjust the seasoning as needed.

9. Generously salt the boiling water. Parcook the shells until very al denté (so you can bite a piece but the inside is still hard and chalky). (7-8 minutes?) Strain and arrange the shells flat-side down on a dish towel. 

10. Spoon heaping tablespoons of the tuna sauce into shells. Arrange them on top of the delicata layer, then tear remaining delicata rings in half and nestle them in here and there between shells. Pour the remainder of the sauce on top.

11. In a small bowl, combine the remaining Parmesan, panko, and freshly ground black pepper. Sprinkle it evenly on top of the saucy shells. Bake until bubbling and golden, 25 to 35 minutes. For a deeply golden crust, you may set the oven to broil in the last 3 minutes.

12. Scoop shells and squash into shallow bowls and garnish with dill sprigs.