Cook the pasta in a pot of boiling salted water according to the package directions.
In a bowl, whisk together the tahini, water, soy sauce, lemon juice, grated ginger, garlic, salt and pepper until smooth. Drain the cooked noodles and toss while hot with the tahini sauce, toss in the steamed veggies.
Top with the chopped scallions, sesame seeds and chili paste (shattah) if you like. Tip: if tahini sauce gets too thick you can thin it out with a bit of water, one tablespoon at a time.