Heat olive oil in dutch oven or stock pot over medium-low heat. Add in the onion and garlic and cook until tender (approximately 5 minutes).
Add the curry powder, coriander, turmeric, cinnamon, ginger, cayenne pepper, and salt to the pot.
Pour in the coconut milk and whisk to distribute the spices.
Add in the butternut squash and tomatoes and simmer on low for 20-25 minutes or until the butternut squash is fork-tender.
Stir in the chopped cilantro with about 5 minutes left of simmering time.
To increase the thickness, I recommend transferring two ladles of the mixture to a blender, blending for 10-15 seconds and returning the blended mixture to the pot.
Ladle the mixture over heaps of brown rice and serve.