In a large skillet heat oil over medium heat. Add onion and saute until softened, 6 to 8 minutes. Add garlic, ginger, serrano peppers, and garam masala and cook, stirring, 1 minute more.
Add coconut milk, soup, and salt, bring to a boil, then reduce heat to simmer gently, partially covered, until thickened, about 20 minutes.
Scrape mixture into a blender and blend until very smooth. Use sauce to simmer vegetables, tofu, or tempeh, or drizzle over cooked grains or grilled vegetables.
This nutritional information refers to each serving of the entire recipe and not just the products used as ingredients.