1. Bring a large pan of water to a boil.
2. Cook pasta according to package directions.
3. Drain and cool pasta down on a baking tray in the refrigerator.
4. Drizzle penne with a small amount of olive oil to prevent sticking.
5. Clean bristles off portobello mushrooms (inside the cap) and discard stems.
6. Marinate in olive oil, salt, pepper and garlic.
7. Place on baking tray.
8. Roast mushrooms in a preheated 200˚C degree oven for about 15 minutes.
9. Allow to cool.
10. Cut into thin julienne slices.
11. Roast peppers over an open flame until almost completely charred.
12. Transfer to a plastic bag.
13. Allow peppers to cool, then peel and seed.
14. Cut into thin julienne pieces.
15. Transfer cooled Penne to a large bowl.
16. Combine penne with olives, peppers, mushrooms and grated cheese.
17. Mix well and serve chilled or at room temperature.