(from Epicurious by Kemp Minifie and Betty Blood Miles)

Serves 4 to 6

• 1 medium onion, finely chopped
• 4 1/2 tablespoons unsalted butter
• 10 oz mushrooms, trimmed and sliced 1/4 inch thick (4 cups)
• 2 teaspoons soy sauce
• 1/4 cup Sherry
• 1/4 cup all-purpose flour
• 2 cups low-sodium chicken broth
• 1 cup whole milk
• 2 teaspoons fresh lemon juice
• 1/4 teaspoon salt
• 1 (6-oz) can tuna in olive oil, drained
• 6 oz dried curly egg noodles (preferably Pennsylvania Dutch style; about 3 1/4 cups)
• 1 1/2 cups coarse fresh bread crumbs (from 3 slices firm white sandwich bread)
• 4 oz coarsely grated Cheddar (1 cup)
• 1 tablespoon vegetable oil

1. Put oven rack in middle position and preheat oven to 375°F.
   Butter a shallow 2-quart baking dish.
2. Cook onion in 1 1/2 tablespoons butter with a pinch of salt in a 12-inch heavy skillet over moderately low heat, covered, stirring occasionally, until softened, about 5 minutes.
   • Increase heat to moderately high and add mushrooms, then sauté, stirring occasionally, until mushrooms begin to give off liquid, about 2 minutes.
   • Add soy sauce and continue to sauté mushrooms, stirring, until liquid mushrooms give off is evaporated. Add Sherry and boil, stirring occasionally, until evaporated.
   • Remove from heat.
3. Melt remaining 3 tablespoons butter in a 2- to 3-quart heavy saucepan over moderately low heat and whisk in flour, then cook roux, whisking, 3 minutes.
   • Add broth in a stream, whisking, and bring to a boil, whisking.
   • Whisk in milk and simmer sauce, whisking occasionally, 5 minutes.
   • Stir in mushroom mixture, lemon juice, and salt.
   • Flake tuna into sauce and stir gently.
   • Season sauce with salt and pepper.
4. Cook noodles in a 5- to 6-quart pot of boiling salted water until al dente.
   • Drain noodles in a colander and return to pot.
   • Add sauce and stir gently to combine.
   • Transfer mixture to baking dish, spreading evenly.
5. Toss together bread crumbs and cheese in a bowl.
   • Drizzle with oil and toss again, then sprinkle evenly over casserole.
   • Bake until topping is crisp and sauce is bubbling, 20 to 30 minutes.