Pour coffee into a small saucepan and sprinkle the gelatin on top. Set for 5 minutes to allow the gelatin to bloom. Add cream, sugar and salt, place the pan on the stove and increase heat to medium, stirring well to dissolve the sugar. Heat for around 3 minutes, being careful the mixture does not boil. Remove from the heat, set aside for a few minutes to cool. Pour the mixture into serving glasses. I used a total of 3 100ml glasses, but did not fill them up completely.

Place in the freezer for 30-40 minutes, stirring very gently every 10 minutes. This is to prevent the panna cotta mixture from separating, as happened to me (if your mixture isn't separating, just place the glasses in the refrigerator and skip this step!). Do ensure to stir gently so as not to splash the mixture up the sides of the glasses.

Once the mixture has set enough and doesn't separate anymore, place the panna cottas in the refrigerator and set for at least 4 hours or overnight.

Just before serving, place the chocolate hazelnut spread in a microwave safe container and warm slightly in the microwave until it's pourable (should take around 15 seconds, don't make it hot!). Gently spoon or pour 1-2 tablespoons of the spread on top of the panna cottas and shake/tilt the glass very carefully to get an even, smooth layer. Repeat with remaining panna cottas. The amount of the spread you need depends on how large your serving glasses are.

Allow to set at room temperature for around 10 minutes, then serve immediately.