Preheat the oven to 350°F (175°C).
Cook egg noodles according to package instructions until al dente. Drain and set aside.
In a large skillet, heat olive oil over medium heat. Add chopped onion and cook for 3-4 minutes until softened.
Add minced garlic and sliced mushrooms to the skillet. Cook for another 5 minutes until mushrooms are tender.
Stir in frozen peas and cook for 2 minutes until heated through.
In a large mixing bowl, combine cooked noodles, sautéed vegetables, drained tuna, chicken broth, sour cream, Dijon mustard, dried thyme, salt, and black pepper. Mix well to combine.
Transfer the mixture to a greased 9×13 inch baking dish. Sprinkle shredded cheddar cheese evenly over the top.
Sprinkle crushed potato chips over the cheese layer for a crunchy topping.
Bake uncovered in the preheated oven for 25-30 minutes until bubbly and the topping is golden brown.
Remove from oven and let cool for 5 minutes before serving.