In a large pot, heat ½ tbsp cooking oil over medium heat. Add in the onion, ginger, and garlic. Cook for about 3-5 minutes until the onions are translucent.
Add cauliflower, summer squash, lemongrass, toasted sesame seeds, and broth to the pot. Bring to a boil, then reduce heat and let it simmer for about 20-25 minutes until the vegetables are tender.
Remove the lemongrass stick from the pot. Use an immersion blender to blend the soup until smooth.
Stir in coconut milk and miso paste, and let it simmer for another 5-7 minutes.
Once done, let the soup cool down and then chill it in the refrigerator for a few hours before serving.
Garnish with cilantro, scallions, jalapenos, or Thai chilies if desired.
Enjoy this chilled lemongrass ginger cauliflower soup!
