Preheat oven to 375°F. In a Dutch oven, cook noodles in heavily salted water for 7 minutes. Drain and transfer to a large bowl, do not rinse. Toss with 2 teaspoons olive oil so the noodles don't stick.
Heat tablespoon olive oil and butter in Dutch oven over medium. Add celery, onion and garlic powder. Cook until tender, about 4 more minutes. Add thyme, berbere spice (or Tabasco), salt and pepper and cook for 2 more minutes, stirring constantly.
Whisk in flour and cook for about 1 minute. Whisking constantly, add chicken stock, milk and cheese. Bring to a boil, reduce heat to a simmer and whisk in Worcestershire sauce and mustard. Simmer 4 minutes and sauce should be thickened.
Drain the tuna and crumble into the Dutch oven. Add the noodles and peas, tossing all to incorporate and get coated.
Pour into 13x9" baking pan coated with cooking spray and bake covered with aluminum foil for 10 minutes. Remove foil and evenly distribute potato chips on top. Return to oven, uncovered, and bake another 5 minutes. Serve immediately.
Berbere is a chile and spice blend used to season many Ethiopian dishes. If you can't find it, substitute with 1 teaspoon of Tabasco in this dish to give it a little kick.
I get an 8 oz bag of Jalapeno Potato Chips (Kettle) and use half of the bag.