Gather all of your ingredients. Prepare the round cake pan with cooking spray, and line with either a round silicone liner or parchment paper. Spray the liner/parchment and set aside.
Preheat your oven to 350℉. Rearrange the racks in the oven to accommodate a large roasting pan where you can easily (and safely!) pour water directly into the pan when you're ready to bake. Place the roasting pan on the rack.
Add the expresso powder to the coffee, and mix thoroughly. Set aside.
In a mixing bowl, GENTLY whisk the cracked eggs and set aside, being mindful not to incorporate too much air. Mix in the vanilla extract and set aside.
Add the butter to the chopped chocolate and set aside.
In a saucepan over medium-high heat, add the sugar, salt and coffee mixture. Cook until you bring just to a boil, then immediately remove from heat. Set aside for at least ten minutes to cool.
While the mixture cools, bring a few cups of water to a boil. This water will be used to create a water bath for the torte.
After cooling, pour the contents of the saucepan over the butter and chocolate, using a spatula to gently stir all of the ingredients together. The batter will be thick and take a few minutes for fully incorporate everything until smooth, so give it time.
Pour the lightly scrambled egg mixture directly into the bowl with the chocolate batter through a fine mesh sieve. This step will allow the majority of the egg whites along with the yolks while straining out the chalaza (the stringy part of the egg white). Use your spatula to fold the eggs into the batter until smooth and fully incorporated.
Pour the batter into the prepared pan.
With your boiling water nearby, open the oven door and place the pan into the center of the roasting pan. Carefully pour the boiling water into the roasting pan, just until it reaches approximately half-way up the sides of the cake pan, being mindful not to splash any water into the cake pan. Shut the door to ensure as much steam stays in the oven as possible.Bake for 45 to 50 minutes. You'll know the torte is done when the sides just start to pull away from the edges of the pan, and a tester (or toothpick) inserted into the center of the torte comes out clean. Allow the torte to cool for one hour, still in the pan, on a wire cooling rack, at room temperature. Once cool, move the torte into the refrigerator for a minimum of 5 hours, or up to overnight. After an hour or so in the fridge, you can feel free to place a plastic wrap cover stretched carefully over the top of the pan, so it does not touch the top of the cake.
To serve, pop the torte out of the cake pan - don't try to cut the slices from the pan. Remove the silicone baking sheet or parchment. Use a sharp knife, preferably run first under very hot water and wiped clean using a paper towel. Repeat in between each portion to keep slice edges clean. Dust tops of the torte with sifted powdered sugar, add fresh raspberries or serve with a raspberry coulis. The tart and sweet of the berries is a perfect balance to the rich, bittersweet of the chocolate.