In a bowl mix together butter and grated parmesan cheese. The butter should preferably be at room temperature otherwise also it works. Meanwhile boil the pasta in salted water till al dente. Take out the pasta with a ladle and put in in the bowl with butter and cheese and stir well. The heat from the pasta will melt the cheese and butter and a smooth rich sauce will be formed which can be made more liquidy or thin with the addition of little pasta water. Serve in bowl as such or garnished with pepper or your choice of spices and herbs or topped with grilled/roasted/steamed veggies.