For the Pesto

1. Bring a large pot of salted water to a boil. Add the kale ribs and stems, cashews and basil stems.  Boil for 10 minutes.
2. Add the kale leaves and cook until tender but not mushy, another 5 minutes.
3. Add the basil leaves and stir just to submerge. Turn off the heat, then use a slotted spoon to transfer everything but the cooking liquid to a blender.  If using an immersion blender transfer to a large bowl.  RESERVE THE COOKING LIQUID.
4. Allow it to cool slightly.

For the Pasta

1. Return the reserved cooking liquid to a boil; add more hot water if a lot evaporated while cooking the pesto ingredients.
2. Add the pasta and cook according to box directions.  Used the shorter cooking time.
3. Reserve 1 1/2 cups of pasta water, then drain.

To Finish

1. To the blender/bowl, add 1/2 cup of the reserved pasta water, the garlic (oil) and the red pepper flakes.  Blend on high until very smooth*.
2. Return the pasta to the pot and add the pesto.  Stir vigorously to combine, adding pasta water as needed to loosen the sauce and help it cling to the noodles (the sauce will thicken as it cools).
3. Add the lemon juice and salt.  Sprinkle with (plant based) grated parmesan and garnish with additional basil.
4. Serve and eat right away.