Uninstall Ubuntu from dual boot with Windows in different drives

I have both Windows and Ubuntu on my machine with dual boot. Windows is on the SSD, and Ubuntu is on a normal hard drive. I've tried the most common solution online, which is booting from a Windows repair USB stick and typing bootrec.exe /fixmbr. But that doesn't work. I've read somewhere that that only works for adjacent Windows and Linux partitions. So, how should I uninstall Ubuntu without any traces?