Preheat the oven to 190 degrees C.

Cook the egg noodles according to the directions on the package. Drain the noodles and set aside.

Combine the soup, milk, sour cream, and mustard powder in a large bowl. Then, stir in the tuna and red peppers and/or peas. Finally, mix in the noodles.

Lightly grease 20cm x 20cm square baking dish with cooking spray. Then, add the noodle mixture to the dish and spread it evenly.

Crumble the biscuits on top of the casserole. Then, take the butter and slice into smaller pieces, dabbing 6-8 pieces around the cracker topping.

Bake for about 25-30 minutes, or until bubbly and browned slightly on top. If you’d like to add a garnish, sprinkle with fresh thyme.

Enjoy!