Measure out 1 cup of frozen chopped spinach, and place the frozen spinach in a heat-safe bowl. Microwave until thawed. When cool enough to handle, transfer thawed spinach to a fine mesh strainer. Arrange the strainer over a large mixing bowl and squeeze spinach, wringing dry, until all excess water is drained from the spinach.
Add spinach, minced garlic, chopped artichokes, diced sun dried tomatoes, and grated parmesan to a large mixing bowl. Stir until well combined.
Spoon mixture into a 24-cup mini muffin pan, filling each compartment about 2/3 of the way to the brim.
Add eggs and mascarpone to a second large mixing bowl. Season with salt and pepper. Whisk until mixture is smooth and well combined.
Transfer egg mixture to a 2-cup measuring cup with a handle and spout. Slowly and carefully pour egg mixture into each muffin cup, filling each nearly to the brim.
Bake in the oven until eggs are firm but still light and airy, about 18-20 minutes.