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 diced onion and cook for 3-4 minutes until translucent.
Add minced garlic and sliced mushrooms to the skillet. Cook for 5-6 minutes until mushrooms are softened.
In a large mixing bowl, combine the dairy-free cream of mushroom soup, vegetable broth, coconut milk, dried thyme, black pepper, and salt. Stir well to combine.
Add the cooked onion, garlic, and mushroom mixture to the bowl. Stir in the drained tuna, thawed peas, and cooked egg noodles. Mix until evenly combined.
Transfer the mixture to a 9×13 inch baking dish and spread evenly.
Sprinkle the crushed potato chips evenly over the top of the casserole.
Bake in the preheated oven for 25-30 minutes, until the casserole is bubbly and the topping is golden brown.
Remove from oven and let cool for 5 minutes before serving.