This roasted broccoli pesto is lightened up in two ways by using an avocado instead of olive oil and also by adding water by the tbsp instead of oil to get the ingredients processing smoothly in the food processor. Feel free to sub oil (around ½ - ¾ cup + couple tablespoons) for both of these ingredients if you prefer. The spinach is also an optional [yet very nutritious!] ingredient that does not alter the taste of the pesto. Pine nuts and Cashews work great in this sauce because they are a "creamier" nut - I would not recommend subbing with another nut that might be more difficult to process in the food processor. This pesto will last for up to a week in the fridge in a sealed container. Feel free to freeze some of the pesto to enjoy at a later time.