Borettane Onions are distinguished by their flat, saucer-like shape - they are a white onion with a mild, sweet taste. My previous experience with these onions was in Florence and that time I purchased them pre-peeled which I must admit does make life a lot easier.
The dish I've made is inspired by an onion and bacon tart - here the onion is replaced by slow-cooked and lightly caramelised borettanes and the bacon is substituted with this Lonza di Maiale.
It is simply a cured pork loin and you could easily substitute pancetta.
500 grams borettane onions, peeled
150 grams diced Lonza di Maiale or Pancetta, diced
½ cup milk
Prepare the onions:
Once peeled, depending on the size of the onions you have, halve any of the larger onions so they are roughly the same size - this will help them to cook evenly.
Make the filling:
Heat a little oil in a pan and saute the lonza or pancetta until crisp. Remove the cooked lonza from the pan - put the pan back onto a gentle heat adding a knob of butter. When the butter has melted, tumble in your prepared onions and let this cook slowly until the onions have softened and are lightly golden. Return the cooked lonza to the pan, stir well and then set aside to cool.
Make the tart:
Line a tart tin with shortcrust pastry and then loosely add in the filling. Whisk the eggs with the milk and a generous handful of grated parmesan and pour over - it should cover the filling. Fold the excess pastry over to give it that rustic look.
Bake in a preheated 170°C oven until the pastry is golden and the filling is puffed and cooked through - around 30 to 40 minutes.
Let it cool a little before serving - add a simple leaf salad and you've got an excellent brunch dish.