
Bloom the gelatin - Place the water in a small bowl. Sprinkle the gelatin over the water and mix to saturate the gelatin with the water. Set it aside to bloom for 10 - 15 minutes (minimum).
Make the panna cotta base - In a saucepan, place roughly half of the milk, the instant coffee, sugar, and salt. Heat over medium heat while stirring to dissolve the sugar and to heat the milk.
When the milk is steaming, or is just starting to simmer, lower the heat.
Add the bloomed gelatin to the milk mixture. Whisk gently to dissolve the gelatin in the hot milk mixture, but do NOT allow the milk to come to a boil. The gelatin should dissolve in the residual heat, so you can turn off the stove at this point as well.
There should be no granules visible in the milk mixture once the gelatin has completely dissolved. Add the vanilla and stir it in to mix.
Make the panna cotta mix - Pour the hot milk and gelatin mix into a jug or bowl. Add the remaining milk and whisk to mix it in. Then add the heavy cream and mix it in with the milk mixture.
Check how warm the panna cotta mixture is at this stage. If the coffee panna cotta mixture is warm, then allow the mixture to cool down to room temperature. You can also place the jug in a cold water bath and whisk the mixture to let it cool down.
Once the mixture is cooled down, whisk it really well to make sure the panna cotta does not set into two separate layers. Or, optionally use a stick blender to pulse the mixture to mix well.
Divide and set the coffee panna cotta - While the panna cotta is cooling down, prepare 6 individual dishes, each with a 150 - 160 mL capacity, to serve the panna cotta.
You can choose to set the panna cotta in molds (like dariole molds made with metal, silicone, or plastic), so that the coffee panna cotta can be unmolded before serving. OR you can set the panna cotta in 150 - 160 mL capacity ramekins or coffee cups, if you want to serve the panna cotta directly in the dish without unmolding it.
Lightly grease the molds (if using), if you want to unmold the panna cotta when serving.
Divide the panna cotta mixture between the 6 dishes (about 130 - 140 mL each). Or pour the panna cotta in one large shallow dish (1 liter capacity) to serve as one dish.
Refrigerate for at least 4 hours (preferably 8 hours / overnight) to set the panna cotta. Larger dishes will take longer to set.
Serve - Once set, unmold the coffee panna cotta onto individual serving plates. Dip the molds in hot water for just 2 - 3 seconds to help loosen the panna cotta if needed. Place the mold upside down on a plate and gently tap on it to loosen and release the dessert onto the plate (see recipe notes below).
Top the coffee panna cotta (molded or unmolded), with whipped cream and chocolate fudge sauce and / or chocolate shavings (or other toppings of your choice). Serve chilled.
Make the chocolate fudge sauce according to the instructions in the linked recipe. But add 1 tbsp of instant coffee granules to the sauce to add coffee flavor. You can add more coffee for a deeper coffee flavor.