Cook egg noodles according to the package. Drain and set aside.
In a large mixing bowl add soup, mayo, tuna, half of the cheese, and peas. Mix well.
Add in cooked noodles and toss to coat.
Pour into a 9x13 greased baking dish.
Sprinkle the fried onions and remaining grated cheese all over the top.
Bake in the oven for 40 minutes until warm and golden.