Start a new master league and set the difficulty to beginner and time per game to the lowest (5 minutes). Then select Bayern Munich as your club from existing clubs. They can be found in the other European clubs category. Because the Bundesliga is not in the game, this means you will be allowed to select which league to play in. I selected the Eredivision (Netherlands) because Bayern has no problem winning every game in the league. With this you can just skip every game, and you will most likely win every game that matters for the achievement. You can make safety saves if you are worried and play games if you wish, but skipping every game worked for me and I had no threat of losing a game.