While starting from scratch is the best way to go about making anything, we'll use a canned version for expediency.
Scoop two tablespoons of dulce de leche from the half cup and set aside
Add espresso, cream, and ice to a blender, pulse until smooth
Spoon into glasses
Drizzle remaining dulce de leche on top of the frappe
To get the most flavor out of your coffee prepare the ice cubes with filtered water. When it comes to tap water versus filtered water for your coffee, filtered is best especially when you consider 99% of coffee is water.
Filtered water will have a bright and crisp flavor to it, removing any after taste of metallic or acidity you can find with some tap waters.
When making a frappé, it is easy to overlook the type of water used in your icecube tray, avoid this rookie frappé mistake by always using filtered water.