In a large lidded soup pot over medium-high heat, melt the butter and add in the onions and carrots. Sauté until the onions are transparent and soft.
Add the minced garlic and sauté for another 2-3 minutes until browned and fragrant. Sprinkle the curry powder over the onion mixture and stir, sautéing for 1-2 minutes, then sprinkle the flour over the mixture and stir, sautéing for another 2-3 minutes.
Slowly add the broth to the flour mixture, whisking rapidly and steadily so that there are no lumps and the mixture is smooth. Stir in the pumpkin, brown sugar and soy sauce.
Place a lid on the pot and simmer on low heat for 20-30 minutes, stirring occasionally, until the vegetables are tender.
Stir in the ravioli. Cook for 5 minutes, then stir in the spinach and the heavy cream. Continue to cook for another 2-3 minutes or until the ravioli is done.