Add just enough water to cover the pasta and boil in a pot. Add butter, salt, and pasta. Stir the pasta constantly until the pasta is al dente. Add water if you need it.
Meanwhile, add 1/2 tbsp butter, garlic, and thyme in a skillet over medium-high heat. Add oyster mushrooms until browned.
Remove mushrooms from the skillet, and set aside.
Add salt, pepper, and white truffle paste to pasta and mix.
Add cooked oyster mushroom to pasta, and toss.
Serve with chopped parsley.