Preheat the oven to 400 degrees and line a sheet tray with nonstick aluminum foil.
Trim the ends from the squash and cut in half lengthwise. Scoop out the seeds and pulp and discard. Drizzle with one tablespoon olive oil and place cut side down on the tray. Roast for about 30 mins or until the squash is tender and can be easily pierced with a knife.
Cool slightly and use a fork to shred the squash into spaghetti strands. Set aside.
On a separate sheet tray lined with nonstick aluminum foil, toss the mushrooms with the remaining olive oil and sprinkle with kosher salt.
Roast for about 15 mins or until the mushrooms are browned and a little crispy.
While the squash and mushrooms are roasting, heat the butter in a large saute pan until melted.
Add the leeks and cook over medium/high heat until golden and tender. Add the garlic and saute for 2 more mins.
Add the wine and cook for 2 mins. Add the squash, parmesan cheese, lemon zest and thyme and toss together. Season to taste with kosher salt and pepper. To serve, top the spaghetti squash with the roasted mushrooms and a sprinkle of parmesan cheese.