In a large pot, heat oil over medium heat. Add diced carrots and diced pumpkin (if using) and stir to coat with oil. Cover pot, reduce heat to medium low and allow to cook for about 10 minutes, stirring a few times to make sure they don't stick. You don't want them to brown. Reduce heat if necessary. (*If using canned pumpkin, just cook the carrots at this point and add the pumpkin puree later)
Remove lid. Add garlic, Thai curry, salt, pepper, cumin and ginger to the pot. Stir and cook for 2 minutes. Add chicken stock, canned pumpkin (if using), coconut milk and shredded coconut .
Cook on medium heat, stirring occasionally, for 35 minutes or until carrots are tender.
Puree with an immersion blender or in small batches in a blender.
Taste, and season with more salt and pepper, as necessary.
Serve, garnished with a dollop of sour cream and fresh cilantro leaves. Very nice with a rustic, crusty bread.
Be sure to read the "Cook's Notes" in the original post, for more tips, options, substitutions and variations for this recipe!