1: Heat the oil over a high heat, add the onion and cook for 5 minutes, or until softened. Add the garlic, carrot and squeezed courgette. Cook for a further 5 minutes, stirring regularly. Tip into a large bowl and leave to cool.
2: When cool, add the sausage meat, lentils, sage, salt and pepper and mix well.
3: Roll out the puff pastry and cut into 2 rectangles each 25cm x 20cm, with the long sides nearest you. Divide the sausage mixture in half. Shape one half into a log down the right-hand side of one piece of pastry, leaving a 1cm border. Fold the pastry from the left-hand side over the filling and seal with a little egg wash and fork the edges down. Repeat with the other piece of pastry and the rest of the filling.
4: Place in the fridge for 30 minutes to firm up.
5: Preheat the oven to 180C fan. Line a baking tray with baking parchment.
6: Remove from the freezer and cut each length into 3 and place on the lined tray. Brush with egg wash and sprinkle with sesame seeds. Cook for 30–35 minutes or until golden brown.
Before you cook the sausage rolls, wrap them well and freeze.
Defrost in the fridge and then cook for 30–35 minutes, until hot all the way through.