Brew coffee or espresso and add cardamom pods. Allow to sit 20-30 minutes, then strain coffee to remove pods.
Prep a loaf pan with non-stick spray and then line with plastic wrap on all sides. Set aside.
Whisk ½ cup of sugar with egg yolks, espresso and salt in a large metal bowl. Place the bowl over a pan of simmering water. There should only be about 1 inch of water on bottom of pan.
Prep a large bowl of ice water. Set aside.
Whisk egg yolk mixture for 5-6 minutes, until thick and creamy. Place bowl into the other large metal bowl with ice water to cool.
In a stand mixer fitted with whisk attachment, or using a hand mixer, whisk heavy cream, starting on low speed for 1 minute then raising speed to high. Add ½ tsp vanilla and other ½ cup sugar until firm peaks form.
Using a rubber spatula, fold the whipped cream into the coffee custard. Spoon mixture into the prepared pan and place in freezer overnight or for at least hours.
When ready to serve, remove semi freddo from freezer. Allow to sit 2-3 minutes, and then place a platter on top. Invert semi freddo onto platter and slice. Garnish with a dusting of cinnamon, cocoa powder or chocolate curls.
