Briefly blanch the scampi (prawns) in boiling salted water for about 30 seconds and refresh in ice cold water.
Remove the shells and cut the tails into half inch pieces.
In a bowl, beat the eggs, seasoning, and chives with a fork for about a minute or until slightly foamy.
Heat the oil in the omelette pan, add the chopped shallot and cook for about a minute without browning.
Add the diced scampi and cook on low heat “for a minute then flame with Cognac. (Be careful when you "flame" the Cognac. It can be dangerous!" Add the crème fraîche and simmer for a few minutes or until sauce has thickened.
Briefly beat the eggs again and add to the pan. Turn the heat down to low and use a fork to scramble the stir the eggs. As the eggs set on the outer edges of the pan, use a fork (or a wooden spatula if you are using a non stick pan) and draw them toward the center of the pan. Repeat as needed while shaking the pan to allow any uncooked liquid set and cook until eggs almost form a large pancake. With a spatula, lift up and fold.
When the omelette sets, slide onto a serving dish. Fold a second time to create a rolled shape with the omelette.
Wipe the pan with a piece of paper towel then add butter to melt. Brush the top of the omelette with the melted butter to make it shiny; this is called to “lustrate” the omelet - it’s a must in the art of omelet making.
Serve immediately.