Preheat oven to 375 degrees.
Measure and prep all of your ingredients first.
Line your baking sheet with parchment paper--make sure it is one huge sheet that you can trim off to hang out over the edges. Overlapping is not recommended! Press into the bottom and up the sides to make sure that egg mixture will not run under the parchment paper or over the sides.
Soften cream cheese and add to a mixing bowl. Gradually whisk in milk until creamy to prevent separating.
Add flour and salt and mix together in cream cheese mixture.
Whisk eggs and add to cream cheese mixture and whisk together until as smooth as you can make it. Don't worry if it looks like bits of cream cheese just floating in the milk...it will still turn out perfectly!
Pour egg mixture into the pan and push the paper down in the corners making sure that the egg mixture fills the entire pan.
Place the pan on the top shelf of your preheated 375 degree oven.
Bake until the omelet is puffy and golden---about 30 minutes or a few minutes longer depending on your oven.
If choosing to make this a vegetarian recipe, mince 1 1/2 C veggies of your choice and saute' in a tiny bit of butter and set aside.
If choosing the ham and cheese omelet version, chop ham and green onions and set aside.
Remove omelet from the oven and immediately spread dijon mustard across the entire surface--don't skip this step--it really makes this recipe!
Sprinkle the surface of the omelet with half of your grated cheese to help begin melting it.
Next, add your ham or veggies to the entire surface of the omelet. Add green onions if you are making the ham and cheese and then top with the remaining cheese.
You may roll jelly roll fashion from either direction...short side to the end which makes it thicker...or from the long end across. I have chosen in the photos to roll from the long side. You choose!Remove the parchment paper as you roll. Let the omelet roll rest about five minutes before serving to allow the cheese to melt.
Lift the parchment paper and move to your serving tray and carefully roll onto the tray.
You may garnish with additional green onions, herbs or cheese.I chose to set mine diagonally in the center of a large serving platter and place a bed of arugula and spinach beneath fruit on either side for serving. Feel free to be creative here! Serve immediately while hot!