Heat vegetable oil in a skillet over medium heat, add asparagus and fry for 10 minutes. Then add mushrooms, turmeric powder, dried oregano leaves, salt and pepper. Cover the skillet and cook until vegetables are tender. Add basil and sliced olives, uncover the skillet, stir and cook until almost all liquid is absorbed.
Meanwhile make the White Sauce or Bechemal Sauce. We need thin white sauce, add more milk and make enough sauce for an ample serving of pasta for four people.
Cook pasta in a large pot of boiling salted water until just tender but still firm to bite. When pasta is ready, drain and toss with the olive oil, then transfer to a serving dish. Gently toss pasta with mixture and white sauce then sprinkle with pepper. Serve immediately.