Whip the heavy cream: Pour 250g heavy cream into a clean, dry bowl and add 25g sugar. Use an electric mixer to start on low speed to combine the cream and sugar, then increase the speed to medium. Whip until the cream thickens and forms soft peaks (when the mixer is lifted, the cream should form a slight curve). Be careful not to overwhip, as this can affect the texture.
Mix in the mascarpone cheese: Take 250g mascarpone cheese out of the fridge and allow it to soften at room temperature for 30-60 minutes. Once softened, add it to the whipped cream and mix using a hand mixer until well combined. Gently fold with a spatula to ensure the mixture stays light and airy.
Assemble the tiramisu: Pour 150g coffee liquid into a shallow dish. Quickly dip each ladyfinger into the coffee, making sure they are evenly soaked but not too soggy. Arrange the dipped ladyfingers at the bottom of your container, pressing them together tightly. Spread a layer of mascarpone mixture over the ladyfingers, smoothing it out with a spatula. Repeat the layering process, adding more soaked ladyfingers and mascarpone mixture. Once done, cover and refrigerate for at least 6 hours (overnight is best).
Make the chocolate shell: In a heatproof bowl, place 90g dark chocolate and melt it over a pot of simmering water (double boiler method). Stir until the chocolate is completely melted. Once melted, add 35g coconut oil and stir until fully incorporated. Then, mix in 40g crushed peanuts.
Pour the chocolate: After the tiramisu has chilled, remove it from the fridge and pour the chocolate mixture over chilled tiramisu, tilting to coat evenly. Ensure the chocolate layer covers the entire surface of the tiramisu.
Freeze to set: Place the tiramisu in the freezer for about 10 minutes to allow the chocolate to set. Don't freeze for too long, as you want the dessert to remain creamy on the inside.
Serve: After freezing, remove the tiramisu from the freezer and let it sit for 1-2 minutes at room temperature before cutting it into 6 pieces. Serve and enjoy your delicious chocolate tiramisu!