Brown the breakfast sausage in a large pan until just cooked through.
In a large bowl, beat eggs together. Whisk in seasonings. Stir in the cheese.
Dice the mushrooms and bell pepper. Add to egg mixture. Stir in breakfast sausage.
Pour mixture into a greased/buttered 8x8 or 9x9 pan. Cook at 350F for approximately 55 minutes, or until golden brown around the edges and just set in the center. Let set on counter for at least 30 minutes to continue cooking slightly and cool off. Refrigerate covered for up to 1 week.
To serve: Cut omelet into six pieces, each piece is one serving. Break the omelet up, sprinkle with extra shredded cheese (I use Monterrey Jack) and Tabasco or Cholula hot sauce, microwave for 60-90 seconds, stir and enjoy!
NOTE: This recipe is very versatile. You can add whatever you want to it. Add some jalapenos or Rotel to make it spicy. Add different meat (ham, Canadian bacon, etc.), or take the meat out altogether. Add different veggies. Add potatoes, hashbrowns, etc. It's up to you! :).