Place the cashews and water into a food processor or blender. Blend unitl smooth, stopping to scrape down the sides of the pitcher or bowl as needed.
Heat the oil in a large pot over medium heat, When the oil is hot, add the onion. Sauté for about five minutes, until softened. Add the garlic and continue to sauté for another minute, until very fragrant.
Stir in the crushed tomatoes, diced tomatoes and vodka. Bring the mixture to a simmer and reduce the heat to-medium low. Continue simmering for about fifteen minutes, until the sauce thickens a bit and the alcohol has cooked off.
Stir the cashew mixture into sauce and bring it back to a simmer, just for a minute, until heated throughout. Remove from heat and season with salt and pepper.
Serve over pasta of choice and garnish with fresh basil or parsley.
Since publishing this recipe, I've gone back and edited the post and updated the recipe to double the batch size, simply because many blending devices aren't large enough to completely blend a small batch of cashews. If you have a smaller device feel free to cut the recipe in half.