In a blender, add sweetened condensed milk and hot coffee. (I make coffee ice cubes with the leftover coffee that won't fit into the blender.)
Blend until smooth and creamy. Ensure all condensed milk on the bottom of the blender is mixed in.
Refrigerate until cold.
Serve over ice and enjoy.
Notes
~TIPS~ I LOVE using flavored coffee with this recipe. My favorite is chocolate mocha, vanilla, mocha, and caramel. This frappuccino is sweet, so you may want to add the condensed milk a little at a time and taste it after mixing. 14 oz (1 can) is the perfect balance for me, especially since I'm serving it over ice, which can water it down, and the coffee cubes are super strong.