1
Preheat oven to 425 degrees. Spray a baking sheet with nonstick spray.
2
Evenly distribute squash, carrots, and parsnip on the baking sheet, and sprinkle with pepper. Bake for 15 minutes.
3
Flip veggies. Bake until softened and browned, about 15 more minutes.
4
Meanwhile, place flour in a medium bowl. Add 1/4 cup cold water, and whisk to dissolve.
5
Spray a large pot with nonstick spray and bring to medium-high heat. Cook and stir onion until browned, about 4 minutes. Add garlic, and cook until fragrant, about 1 minute.
6
Carefully add broth and flour mixture to the pot. Cook and stir until onion is soft, about 5 minutes.
7
Transfer half of the soup to a blender. Add milk, and half of the roasted veggies. Puree. Return pureed mixture to the pot, along with remaining roasted veggies.
8
Return to medium-high heat. Cook and stir until hot and well mixed, about 2 minutes.