In a medium bowl, combine cream cheese, sour cream, onions and spices and blend until smooth.
I like to use a handheld food chopper to chop the jalapeno and onions easily.
Add the chopped jalapeno and canned diced tomatoes and stir in with cream cheese mixture.
Then add fresh baby spinach and shredded cheese. Yes! The spinach will stir in ok--just stir in slowly.
Bake at 350°F in oven safe baking dish. Recipe link also has instructions for making this dip in the slow cooker.