Line a loaf pan (9-by-5-inch works best) with plastic wrap, letting the edges hang over and allowing enough extra plastic to wrap the semifreddo.
In a large bowl, combine the instant coffee, coffee extract, vanilla and 1 pint of the heavy cream. Use an electric mixer to whip until medium to firm peaks form. Use a spatula to gently fold in the condensed milk. Transfer half of the mixture to the prepared loaf pan and freeze until just beginning to set, about 20 minutes.
Microwave 1/2 cup of the hot fudge with the remaining 1 tablespoon heavy cream in a microwave-safe bowl for 20 to 25 seconds, just to loosen it slightly. Spoon it lengthwise down the center of the pan, from end to end.
Transfer the remaining cream mixture to the loaf pan on top of the fudge. Use a butter knife to make swirls going through the mixture. (This will move the fudge throughout the mixture.) Wrap with plastic wrap and place in the freezer for 6 hours.
Before serving, let stand at room temperature for 5 minutes.
Meanwhile heat the remaining 1/4 cup fudge. Unwrap the plastic, invert onto a serving plate and remove the plastic entirely. Drizzle with the hot fudge and sprinkle with the chopped espresso beans. Slice and serve immediately.