Heat a medium stock pot over medium-high heat and spray with cooking spray. Add Thai red curry paste and, using a wooden spoon, gently heat for about 30 seconds.
Whisk in the coconut milk and pumpkin. Whisk until smooth. Pour in chicken broth and continue to whisk until smooth. Heat on high until it comes to a light boil then reduce to low. Simmer for 10 minutes. Season with salt and pepper to taste before serving.