I usually cook with cream of mushroom soup ONLY if I can find the organic variety. Popular non-organic brands contain MSG and other GMOs that we refuse to consume in my household. Alternatively, it's very easy to make your own cream of mushroom soup by sauteing sliced mushrooms with butter and heavy cream over low heat.
Boil egg noodles in a large pot with 1 teaspoon of salt for about 10 minutes. The noodles should be slightly under-cooked or al dente. Remove from heat and drain.
Saute diced onion in the butter. Once onions begin to caramelize, add the minced garlic. Continue to saute until the garlic turns golden, about 30-45 seconds, then remove from heat immediately to stop the garlic from cooking.
In a large bowl, gently fold ingredients together: tuna, Rotel, Cream of Mushroom, onions and garlic, 1 cup of shredded cheese, pasta and crushed red pepper.
Pour mixture into a 9x12 casserole dish and top with the remaining cup of cheese.
Bake for 20-30 minutes or until bubbly.
Remove from oven promptly and let cool 15 minutes. The casserole will continue to cook and set during this time.