Peel the onion and chop it finely. Clean the broccoli stalk and cut it into florets.
Cut the Fontina PDO into cubes removing the rind and keep it aside.
In a cast iron pan, add a little extra virgin olive oil and brown the onion. Add the broccoli florets and cook for a few minutes. Add half a glass of water and leave to soften for 10 minutes. Add salt and pepper to taste. Add the crumbled sausage and cook over high heat.
Pour the dough into a bowl and keep the cast iron pan aside.
Mix two eggs, fresh cream, diced Fontina PDO and fresh thyme in a bowl. Add salt, pepper to taste, and mix well.
Spread the shortcrust pastry on the bottom of the oiled pan, place the broccoli and the sausage in the centre and top with the egg mixture.
Fold up the shortcrust pastry edges, brush with a whisked egg yolk and a little milk and bake in a preheated oven at 180°C for 20 minutes.