Add the cream cheese, mozzarella cheese, grated parmesan, artichoke hearts, garlic, salt, and pepper to a medium saucepan over medium-low heat. Stir to combine and cook until the cream cheese is melted, about 2 to 3 minutes.
Add the spinach to the saucepan in batches, if needed, and cover. Cook until the spinach is wilted, about 3 to 5 minutes, then stir well to combine.
Once all the spinach has been incorporated, stir well and transfer to a shallow dish to cool. Let the dip cool to almost room temperature before moving onto the next step.
When you're ready to make the phyllo shells, remove them from the freezer and thaw on the counter for about 10 minutes. In the meantime, preheat the oven to 350 degrees F.
Space out the phyllo shells on one or two large baking sheets. Then, spoon about 1 tablespoon of the spinach dip into each phyllo shell.
Bake for 6 to 8 minutes, until the shells are golden and crispy and the dip is warmed through. Serve immediately.
Notes
Where to find frozen mini phyllo shells: You can easily buy premade phyllo cups at the grocery store. They’ll be in the freezer section, typically stocked with other pastry doughs like frozen puff pastry.Make ahead instructions: There are a few ways to make this easy appetizer ahead of time.
Prepare the dip no more than 3 days ahead, and store in the fridge until you're ready to make the phyllo cups. While the phyllo thaws, reheat the dip in the microwave for about 2 to 3 minutes (stir halfway through) so that you can easily spoon it into the shells. Then, bake as normal and serve.
If you're bringing these to a potluck, we recommend filling the phyllo shells with dip and then bringing them to the event - unbaked - in a foil tray. When you get there, pop them in the oven and bake as normal so you can serve them fresh and hot!
Serving size and suggestions: These mini spinach artichoke dip phyllo cups are the perfect individual size appetizers to serve at holiday parties - they'll be a hit at Easter, Thanksgiving, or Christmas! Plan to make about 3 to 4 per person, and maybe save a few extra for yourself :)Scaling: One full batch of spinach dip fills about 45 phyllo shells. If you want to make less than that, you can still make a full batch of dip and enjoy the extra dip with pita chips or crostini. Or, you can always halve the entire recipe to make about 2 dozen phyllo cups. If you want to make more than 45, simply 1.5x or 2x the ingredients!