8 (about 75gm) slices flat pancetta 100 gmtreviso leaves2 tspolive oil4eggs, whisked and seasoned to tastePecorino besciamella150 mlmilk1fresh bay leaf80 gmbutter15 gmplain flour60 gm (¼ cup)finely grated Pecorino Romano
For besciamella, combine milk and bay leaf in a saucepan over medium heat, bring to the boil and keep warm. In a separate saucepan, melt butter, then add flour and cook, stirring frequently, until just starting to colour. Remove saucepan from heat and gradually whisk in warm milk. Return pan to heat and cook, stirring frequently, until sauce thickens and coats the back of a wooden spoon. Remove bay leaf, add Pecorino, season to taste and cool.
Cook pancetta in a frying pan over medium heat for 3 minutes or until starting to colour, scatter over treviso, cover and cook for 2 minutes or until wilted, then season to taste.
For frittata, preheat grill to high. Heat oil in a 25cm-frying pan over medium heat, add egg and cook until almost set, then place under grill and cook for 2 minutes or until set. Slide frittata out of pan onto a work surface, spread with besciamella, arrange pancetta mixture on top, roll up to form a cylinder, wrap tightly in baking paper, secure with kitchen twine and refrigerate for at least 2 hours. To serve, unwrap frittata, slice into 1cm-thick slices and serve at room temperature.