Heat oven to 400?F. In a medium bowl, combine cream cheese, sour cream, garlic, oregano, red pepper flakes, and 1/2 teaspoon of salt.

Fold in 1 cup of mozzarella and all but 2 tablespoons of Parmesan.

Transfer the mixture to a shallow broiler-safe 1-quart baking dish. Top with pizza sauce; sprinkle with remaining mozzarella and Parmesan, then pepperoni.

Bake until bubbling and cheese is beginning to brown, about 15 minutes, broiling 1 to 2 minutes if needed.

Let the dip rest for 5 minutes before serving. Serve with baguette slices for dipping.