Meanwhile, saute the veggies by heating a large skillet over medium heat. Add oil, then garlic. Cook for about 30 seconds, until fragrant, then add butternut squash. Cover and cook for 5 minutes before adding mushrooms and kale, then add salt. Cook an additional 5 minutes, stirring occasionally.
When pasta is done, drain and add to skillet; stir well. Turn off heat.
To make the lemon dressing: In a small bowl, add all ingredients and whisk together with a fork until smooth and creamy. Pour over pasta and veggies; mix well to coat.
If you don't have (or don't prefer) butternut squash, swap with sweet potato!
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