Grate or cut the courgette, put in a colander above a bowl, and sprinkle generously with salt.
Prepare a Pyrex glass tray by greasing it with butter and dust it with breadcrumbs.
Preheat the oven at 180 degrees Celsius.
Separate the eggs into whites and yolks.
Start by making the Mornay sauce. Heat 50 grams of butter in a small pan.
When the butter is melted, add the flour.
Fry for a little bit, and start mixing. You will end up with a dough-like mixture.
Start adding milk, little by little, hydrating the flour and butter.
The more milk you add, the more loose the dough will become.
When the milk is finished, you should have a very creamy sauce.
Take the pan off the heat and let it cool down for 10 minutes.
Add the egg yolks and ¾ of the cheese to the mix, and incorporate well.
Drain the courgettes and squeeze them in your hands, to remove the water excess. Then add them to the mix.
Add the ground pepper, minced garlic, and the dill, and mix well. You should have a thick but creamy batter.
In a mixer, whisk the egg whites with a little bit of salt until stiff. Then fold it gently into the batter.
Pour the batter into the prepared Pyrex tray, top with the rest of the cheese and butter cut in flakes, and bake for 35-45 minutes. You will notice the souffle will rise considerably in the oven.
Enjoy hot or cold.