Soak cashews: Transfer the cashews to a small saucepan with enough water to cover by about 2 inches. Bring the water to a gentle boil. Gently boil the cashews for 10 minutes. Set aside.
Cook the kale: Heat a drizzle of olive oil or water in a large skillet over medium-high heat. Add the kale stems and cook for about 3 minutes or until tender. Add the leaves and cook them with the stems for about 2 minutes more, or until softened. Remove the kale from the heat. Add the mustard powder and mix well.
Grind cashews: Drain the cashews, reserving the water. Transfer them to the canister of a food processor. Pulse until finely minced, adding the cashew cooking water, 1 tablespoon at a time as needed, until the cashews are pureed. Scrape down the sides between blending for even mincing.
Combine: Add the kale stems and leaves, white beans, artichoke hearts, garlic, nutritional yeast, lemon zest and juice. Blend until almost smooth, adding the liquid from the jarred artichokes until the desired texture. Add salt and pepper to taste.
