Artichoke, Spinach & Sun-Dried Tomato Dip

"Update: My recipe was just published in the Taste of Home Holidays & Celebrations 2011 Cookbook. Tangy & creamy, this artichoke dip boasts the colorful addition of sun-dried tomatoes. Serve with plain or multi-grain baked tortilla chips. Developed for Ready Set Cook #11 - January 2008 Update 2/27/2013: Thanks to Racrgal for a really productive conversation regarding making this recipe in advance. That led me to run a series of tests. *I made four versions and found that it can be made a day in advance and refrigerated before baking, or made months in advance; frozen and then thawed before baking. Both oil-packed and dry-packed sun-dried tomatoes were tested to make sure the oil did not cause bleeding during thawing...."