In a food processor or coffee grinder, grind raw cashews until a flour-like consistency. Transfer to a medium size bowl.
Using a microplane or zester, grate the garlic cloves into cashew flour.
Add to the cashew mixture, the nutritional yeast, mustard, salt, pepper, lemon juice and water. Whisk to blend.
Place a fine mesh strainer over a medium sized pot. Pour cashew mixture into strainer and gently coax through with the back of a spoon. Discard any small bits left over.
Heat cashew mixture, stirring frequently, over medium-low heat until just hot. It will thicken quickly, so remove from heat once desired consistency is achieved.
Meanwhile, give broccoli and spinach a quick heat. Place in a steamer, or in a pot with a small amount of water, and steam until broccoli is just tender, and spinach is just wilted.
Boil pasta according to package directions. Drain cooked pasta in a colander.
Empty pasta into a large bowl or serving plate. Top with cashew sauce and vegetables. Give a gentle toss to mix.
Serve.