Tiramisu has been replaced by Aroma, therefore making it outdated and not supported anymore. This guide will show you how to move from Tiramisu to Aroma.
Aroma is an environment like Tiramisu, so they are launched the same way, but it offers more features compared to Tiramisu.
In order to use services like Pretendo, you will need Aroma, as they have ended support for Tiramisu.
Please note that the Homebrew Launcher is no longer used on Aroma.
Instructions
If tiramisu has stopped working for some reason, redownload it from the Tiramisu Website.
Section I: Getting Aroma
Download the latest release of the AromaUpdater (the Tiramisu release).
Extract and copy the wiiu folder to the root of your SD Card.
Insert the SD Card into the Wii U and boot into Tiramisu.
Launch Mii Maker to launch the Homebrew Launcher, and then load the AromaUpdater.
Tick whatever additional plugins/modules you may want. Just the default selected (EnvironmentLoader and Base-Aroma) is also fine.
Press + (Plus) to start the installation.
Once finished, press A to reboot the console.
If tiramisu has stopped working for some reason, redownload it from the Tiramisu Website.
Click on Download Payloads and Download Base Aroma
Extract and copy both of the wiiu folders from the two zips to the root of your SD Card.
If your computer asks you to overwrite existing files on your SD Card, you will need to click "Yes". If you are on a Mac, you will need to click "Merge" for folders.
Insert the SD Card into the Wii U and boot it up.
Section II: Booting Aroma
Launch the Environment Loader:
If you coldboot Tiramisu, hold X while the console is booting to get there.
If you didn't coldboot Tiramisu, hold X while launching Health and Safety.
Clear Tiramisu as the default environment by pressing X.
Select Aroma and press Y to set it as the new default environment, then press A.
The Boot Selector will show. Press Y on the Wii U Menu as previously done and press A.
Once you finally boot into the Wii U Menu, you will see apps on your home screen, and have successfully switched to Aroma. Congrats!
Although Tiramisu is outdated, you don't need to delete it. If you still decide to use Tiramisu in the future, for legacy homebrew purposes, just launch the EnvironmentLoader again to select it.