In a food processor, add the cashews, nutritional yeast and garlic. Pulse gently, so that the ingredients are mixed but the cashews are still chunky. Empty into medium-sized bowl and set aside.
In the food processor, add the olive oil and lemon juice first, and then the rocket. Pulse to blend well.
Mix rocket mixture into cashew mixture, and season with salt, pepper and crushed red chili pepper (if using).
Serve with thick crostini-type crackers. May be stored in the fridge up to 3 days.