Sauté onion and garlic in small pan (you could just put them in the crockpot without cooking them first, but this tastes best.)
Place sautéed onion and garlic in slow cooker along with artichoke hearts, spinach, almond milk, feta, parmesan, and pepper. Stir until well combined. Top with cream cheese. Cover and cook on high heat for 2 hours or on low heat for 3-4 hours.
Uncover and stir until everything is well combined. Keep on warm setting until you are ready to serve. (Note: if you are re-heating the dip you may add milk 1-2 tbs at a time if needed if it starts to get dried out on the warm setting.) Enjoy with veggies, whole grain crackers or bread, baked chips, or pretzels if desired.