Squeeze the water from the spinach and cook off in the butter or oil on a medium heat, along with the garlic, till soft.
Add cream cheese and stir till well blended. Add the artichokes and mix well. Add all remaining ingredients and stir until everything has blended and the cheese has melted.
Serve dip hot
Notes
If you don't have onion powder, replace it with 1/4 onion finely chopped or 2 spring onions finely chopped and saute in butter/oil until soft, before you add the spinach in step 1.