Step 1

Coat a 3 1/2- or 4-quart slow cooker with cooking spray; set aside. Squeeze spinach dry, reserving 1/3 cup spinach liquid. In prepared cooker combine spinach, the 1/3 cup liquid, artichokes, onion, mustard, garlic, oregano, and pepper.

Step 2

Cover and cook on low-heat setting for 2 1/2 to 3 hours or on high-heat setting for 1 1/2 hours. Turn off cooker; stir in mayonnaise, sour cream, Parmesan cheese, Italian cheese blend, and lemon juice.