Heat the olive oil in a medium pot. Over medium heat, saute the onion, garlic and celery for 5 minutes, or until they begin to turn translucent
Add the carrot and potato and saute for an additional 5 minutes
Add the broccoli florets, vegetable stock and cashews. Simmer 20-30 minutes, or until the vegetables are soft
Allow the soup to cool slightly. Add the mustard, dill, nutritional yeast, lemon juice, salt and pepper
Blend on high until very smooth. Taste and adjust seasoning
Store in an airtight container up to 5 days in the fridge, or in the freezer up to 1 month