01 -
Preheat your oven to 400°F (200°C).
02 -
Bring 4 quarts of water to a boil in a large pot. Add a tablespoon of salt. Add the egg noodles and cook until almost al dente (about 2 minutes less than package instructions). Add the chopped broccoli to the pot and continue cooking for 2 more minutes. Drain everything in a colander.
03 -
While the pasta is cooking, dry sauté the sliced mushrooms in a frying pan over medium-high heat (no oil needed). Cook until they release their moisture and begin to brown, about 5-10 minutes. Set aside.
04 -
In a large oven-proof pan, melt the butter over medium heat. Add the chopped onion and cook until soft and translucent, about 5 minutes.
05 -
Return the drained pasta and broccoli to the pot. Add the cooked mushrooms, drained tuna, cream of mushroom soup, grated cheddar cheese, milk, and cream. Season with salt and pepper to taste. Stir gently until everything is well combined.
06 -
Transfer the mixture to a 9x13 inch baking dish if not already in an oven-proof pan. Sprinkle the crushed potato chips evenly over the top.
07 -
Bake in the preheated oven for about 20 minutes, until the topping is golden brown and the casserole is bubbling around the edges.