I begin by spraying the inside of the slow cooker with cooking spray so the dip won’t stick. Then I load in all the fresh baby spinach, tearing big leaves to bite-size pieces so every mouthful is tender.
Next I drain and roughly chop the artichoke hearts, then cut the cream cheese into cubes and place both on top of the spinach. Cubing the cream cheese ensures smoother melting.
Then I toss in shredded mozzarella, sour cream, diced onion, minced garlic, and freshly shredded Parmesan. I cover the slow cooker and set it on LOW for two full hours.
After about one hour I remove the lid and give everything a good crank with the spoon so nothing is sticking and ingredients are mixing. Then I cover again and cook for another hour. When done, I stir, season with salt, pepper, and cayenne, then it’s ready to serve.