Preheat the oven to 425ºF.
Cook the pasta until al dente.
Roast the chickpeas: Rub the chickpeas between the layers of a kitchen or paper towel to dry. Transfer to a medium rimmed baking sheet and toss with olive oil, garlic powder, paprika, ground mustard seed, and salt to taste. Bake for about 12 minutes, or until crispy. (Optional: Broil for 2 minutes more for extra crispy.)
Make the sauce: Transfer the cashews, dissolved miso, garlic, onion powder, lemon juice and zest, and nondairy milk to a blender. Blend on high until smooth.
Combine and warm: Transfer the sauce to a medium saucepan. Add the artichoke hearts and spinach. Mix and heat until warmed through. Add water as needed until the desired consistency. Season with salt and black pepper. Add the desired amount of cooked pasta.
For serving: Top with the roasted chickpeas.
