Put the prepared vegetables and the garlic on a baking sheet and drizzle them with olive oil. Season them with 1 teaspoon salt and 1 teaspoon freshly cracked black pepper. Roast them until the vegetables have begun to brown, about 15 to 20 minutes. Remove them from the oven and set aside.
Start preparing a roux in the Dutch oven by melting the butter over medium-high heat. Add the flour and stir constantly for 5 minutes. Immediately add the vegetable mixture and any extra juices to the roux. Stir until incorporated. Season with the cumin and remaining salt and pepper. Reduce the heat and simmer for 30 minutes.
Stir the cilantro and cream into the vegetable mixture and warm it over low heat. Adjust the seasoning, if necessary. Transfer the soup to a serving bowl and enjoy! (Chefs Note: Do not return to a boil once the cream has been incorporated.)