In a large saute pan, over medium heat, melt 2 tablespoons of the butter. Stir in the flour and mix well. Cook for 1 minute. Whisk in the milk and cream slowly and bring the sauce to a boil. Reduce the heat to a simmer and cook until the sauce coats the back of a spoon, about 3 minutes. Stir in the spinach and season with salt and pepper. Continue to simmer for 1 minute. Remove from the heat and keep warm. In another saute pan, over medium heat, melt the remaining butter. Add the artichoke bottoms to the pan and saute for 2 minutes. (just to heat the artichokes through) Season the artichokes with salt and pepper. Cover the pan with a lid and remove from the heat. Bring a pot of salted water to a boil. Add the vinegar to the water. Crack each egg into a small cup. Carefully side one egg into the water. When the water has come back to a slight boil, side in another egg. Continue the process until all the eggs are in the water. Reduce the heat to a simmer and cook until the eggs are set, about 2 to 2 1/2 minutes. Remove the eggs from the water and drain on a paper-lined plate. Season the eggs with salt and pepper. To assemble, spoon the creamed spinach in the center of each artichoke bottom. Place the filled artichokes on a platter. Lay the poached eggs directly on top of the creamed spinach. Drizzle the hollandaise over the poached egg. Garnish with parsley.