Tuna Noodle Casserole

Ingredients

• Nonstick cooking spray
• Kosher salt and freshly ground black pepper
• 300g medium shell pasta
• 4 tbsp unsalted butter
• 1 stalk celery, finely diced
• 1 yellow onion, finely diced
• 2 cloves garlic, minced
• 32g all-purpose flour
• 500l chicken/veg broth
• 250ml whole milk
• 250ml frozen peas
• 60g finely grated Parmigiano-Reggiano
• 1 lemon, zested and juiced
• 3 tbsp parsley
• 2 cans flaked tuna, drained
• For the Topping:
• 500ml crushed plain crinkle cut crisps
• 58g grated Cheddar
• Pinch smoked paprika, optional