Preheat oven at 180°C. Grease a baking tray with butter.
Heat oil in a non-stick pan. Add garlic, mushroom, salt, crushed peppercorns, corn kernels and 1 tsp butter. Toss to mix and sauté well.
Add cream and mix well. Switch off heat.
Add cheese and mix well. Add fresh parsley and mix again. Cool the mixture to room temperature.
Brush melted butter on 1 filo sheet. Place another sheet on top and brush with butter. Place third sheet on top and brush again with butter. Place fourth sheet on top and brush with butter again. Press the arrangement.
Place cooked mixture on the centre of the filo sheet arrangement in a horizontal manner. Fold both sides like an envelope and tightly roll sealing the edges with melted butter. Brush melted butter once again on top and make three slits on top.
Place the roll on the greased baking tray and put in the preheated oven. Bake for 18-20 minutes.
Remove from oven and cut into slices. Serve immediately.