Preheat oven to 400 degrees and line with foil. Spray with cooking spray and scatter the squash slices in a single layer on the pan.
Drizzle the squash slices with olive oil and toss to coat on both sides. Sprinkle with cinnamon, half of the salt (1/2 teaspoon) and pepper then toss again. Bake until golden brown and tender, about 25-30 minutes.
While the squash is roasting, whisk together tahini, lemon juice, garlic and remaining salt in a small bowl. Add warm water, 1 tablespoon at a time, until you've reached desired consistency. Drizzle over roasted squash to serve.
Serving Size: 1/4 of the pan and 1/4 of the tahini sauce