Preheat the oven to 200C/400F/Gas 6.
Chop the vegetables into bite-sized pieces. Garlic cloves should be skinned and left whole. Place in a roasting tin.
Mix the oil with the herbs and seasoning, and the lemon juice if using.
Pour over the vegetables and toss thoroughly. Place in the preheated oven and bake for 30-40 minutes until the vegetables are tender and well browned, then leave to cool.
Take three sheets of filo pastry.
Brush one sheet with olive oil or melted butter, place the second sheet on top and repeat, then top with the third.
Place the cooled roast vegetables onto the filo and roll up to make a sausage shape, tucking the sides in as you go.
Place on a baking sheet, brush with more oil or butter and bake at 200C/400F/Gas6 for about 20 minutes.