Preheat the oven to 425 F. Cook the egg noodles according to package instructions, drain, drizzle a little olive oil over them so they don’t stick together, and set aside.
Make the topping by combining all ingredients in a small bowl until well mixed together
Melt the butter over medium-high heat and saute the onions, celery, and red bell pepper until tender. Season with salt, pepper, and oregano
In a large bowl add the sauteed veggies, cooked noodles, drained tuna, peas, soup, milk, cheese and parsley, mix until well combined
Spoon mixture into a 9x13-inch casserole dish
Sprinkle the topping evenly over the casserole and bake for 20 minutes or until golden brown