Preheat oven to 220 degrees C. Place butter and crushed garlic into a microwave proof jug and cover. Cook in microwave until ingredients are melted together then stir the chilli paste into the garlic buttter mixture.
Peel and chop potatoes into medium sized chunks and put them into a dish that can cook in both microwave and conventional ovens. Pour the garlic/chilli mixture over potatoes and cover the dish with clear plastic wrap.
Microwave for 10 minutes on high, remove plastic wrap and cook uncovered in the conventional oven till golden-about 30 mins. Check and stir after 15 minutes.