In a food processor or blender, combine the 2 heads of roasted garlic cloves, 2 tablespoons of Pompeian olive oil, & ¼ cup of the heavy cream. Blend until the garlic is pulverized. Into the garlic mixture, pour in the remaining ¾ cup heavy cream, heaping ¼ cup sour cream, & ½ cup shredded Parmesan cheese. Season to taste with salt & pepper. Blend the mixture for 30-60 seconds until everything is combined. The mixture will be thick & slightly lumpy, which is perfectly normal! Set the sauce aside.
Melt 3 tablespoons of butter in a large skillet. Add your tortellini & toss the pasta around in the melted butter to coat. Pour the sauce on top of the pasta, & stir gently to combine. Cook on medium heat for 10 minutes, stirring gently occasionally. The sauce will thicken.
Sprinkle on ¼ cup to ½ cup of shredded Parmesan cheese (depending on your tastes), stir to combine and remove from the heat. Pour the tortellini into a serving vessel, & garnish with chopped fresh parsley if desired.