Heat a large skillet with olive oil, add 4 cloves garlic, mushrooms, and asparagus. Season with salt, pepper and Sauté for 3-4 minutes, stirring frequently, until the mushrooms are slightly browned, and the asparagus is tender. Remove from skillet and set aside. (If you prefer more tender asparagus, cook longer. If you prefer it with more bite, cook 2-3 minutes.)
At this time, bring a large pot of water to a boil and season generously with sea salt. Add pasta and cook according to package instructions, then drain and set aside.
In a bowl, whisk lemon, Tahini and salt until well blended, add in water 1 tbsp at a time, until sauce reaches a nice consistency.
Add cooked drained pasta directly to the sauce along with sautéed asparagus and mushrooms. Toss to coat and enjoy immediately