In a large saucepan, cook the ditalini pasta according to package directions, reserving 1/3 cup cooking water. Drain and set aside.
Into the saucepan used for the pasta, over medium-low heat, add the butter. When the butter is melted, add the garlic and cook for 1 minute, until very lightly golden in color.
Add the peas, reserved pasta cooking water, and salt. Bring to a simmer, then cover and cook for 5 minutes.
Using a slotted spoon, remove half the peas and set aside.
Using an immersion blender, or transferring to a stand blender, puree the mixture until the consistency is smooth.
Add the cooked ditalini to the saucepan, then stir to coat.
Add the reserved peas then use salt to adjust the seasoning to taste.
Top with chopped basil and remaining 2 tablespoons Parmesan cheese, then serve warm.