Preheat oven to 425° Fahrenheit.
Soak cashews in a heat-safe bowl with boiling water for 5-10 minutes, then drain.
Add soaked and drained cashews to blender along with the non-dairy milk, nutritional yeast, lemon juice, garlic powder, onion powder, and salt. Blend until super smooth and no lumps remains.
Add drained artichoke hearts and fresh or frozen spinach to blender and pulse 2-3 times to finely chop the veggies.
Transfer to an oven-safe dish or skillet and bake for 20 minutes, or until lightly golden brown and bubbly.