Line two large baking trays, and, using a spatula, divide the meringue into two even circles of meringue. They should be about the size and height of a cake.
Place the pavlovas in the oven, and set the timer for 20 minutes. The pavlovas should be browned, but still slightly soft to the touch.
Turn the oven down to 120˚C, and continue to cook the meringue for an additional hour, checking to ensure it doesn’t become overly browned. Once the meringue has cooked, turn the oven off, and allow it to sit in the cooling oven for 2 hours, or overnight.
To make the coffee syrup, combine the coffee and the 4 remaining tablespoons of caster sugar in a small saucepan on a medium heat. Allow to bubble and thicken, until a viscous syrup has formed, and then remove from the heat.
To assemble, place the first pavlova on your serving platter, and drizzle it with half the coffee syrup, and your desired amount of condensed milk. Layer the second pavlova on top, pressing down very gently, and repeat with the remaining syrup. You may have some syrup and condensed milk left over, depending on your taste. Serve and consume immediately.