How to Make It
Preheat the oven to 375°. In a large, deep skillet, melt the butter in 2 tablespoons of the olive oil over moderate heat. Add the onion and celery and cook until tender, about 8 minutes. Stir in the mushrooms and cook until softened, about 5 minutes. Add the thyme and cook until fragrant, about 1 minute. Stir in the milk and cream cheese and cook until a smooth, thick sauce forms, about 2 minutes. Remove from the heat. Add the Worcestershire sauce and gently fold in the tuna and the peas. Season with salt and pepper.
In a large pot of boiling salted water, cook the egg noodles until al dente. Drain the noodles and rinse under cool water. Add the noodles and 1 cup of the cheddar to the sauce and mix until the noodles are well coated. Spread the noodles in a 2 1/2 quart baking dish.
In a small bowl, toss the panko with the remaining 1 tablespoon of olive oil and season with salt and pepper. Mix in the remaining 3/4 cup of cheddar and sprinkle over the noodles. Bake for about 45 minutes, until the noodles are piping hot and the casserole is golden on top.