Prepare the ingredients: drain the 14 oz artichoke hearts and coarsely chop them; drain the 4 oz can diced jalapeños; thaw the 10 oz frozen spinach and press or squeeze out as much liquid as possible; press 2–3 garlic cloves; measure 8 oz cream cheese, 16 oz light sour cream, 8 Tbsp unsalted butter, and 1 1/2 cups shredded Parmesan cheese.
Place a medium pot over medium heat and add the 8 Tbsp unsalted butter. Melt the butter, swirling the pot occasionally.
Add the 8 oz cream cheese (cut into chunks if desired) to the melted butter and stir until the cream cheese is softened and starting to melt.
Pour in the 16 oz light sour cream gradually while stirring, until the mixture is smooth and combined.
Stir in the 1 1/2 cups shredded Parmesan cheese and continue stirring frequently until the cheese is melted and the mixture is smooth and beginning to bubble gently. If it bubbles too vigorously, reduce the heat to medium-low.
Add the chopped 14 oz artichoke hearts, drained 4 oz diced jalapeños, and the well-drained 10 oz spinach to the pot. Fold them into the cheese mixture until evenly distributed.
Stir in the 2–3 pressed garlic cloves and heat everything together for 2–3 minutes, stirring occasionally, until the dip is hot and the flavors are combined.
Remove from heat and serve hot with chips, crackers, or toasted baguette slices.