“We’re looking forward to Tuesday – I hope that we can show what makes us strong and leave Dortmund’s stadium with a smile,” added Mueller.
Signal Iduna Park would normally be packed with 82 000 fans for a visit of Bayern, but the terraces will remain empty on Tuesday.
“It will still be a hard day’s work,” Mueller added.
“We’re marching, Dortmund is marching.”
The Portugal star also netted twice in the 4-0 rout of arch rivals Schalke the previous weekend in the Ruhr derby.
Dortmund are waiting on the fitness of key defender Mats Hummels, who injured his Achilles’ tendon at Wolfsburg.
In the Bayern camp, midfielder Thiago Alcantara has a groin strain while centre-back Jerome Boateng picked up a leg knock on Saturday.
“I hope we can get the next victory,” said Dortmund’s Swiss centre-back Manuel Akanji.
“Since I’ve been here, we’ve always lost to Bayern away, but won at home. I want to keep this series going.”
Tuesday’s showdown will also pit the league’s top-scorer Robert Lewandowski, 31, who has scored 27 goals in 25 games for Bayern, against his former club.
For the hosts, Norwegian sensation Erling Braut Haaland, 19, has scored ten goals in as many league games since joining Dortmund in January from Salzburg.
Haaland and Lewandowski have exactly the same record – 41 goals from 35 games in all competitions this season.
England winger Jadon Sancho came off the bench to set up Achrif Hakimi for the second goal in Wolfsburg.
Dortmund coach Lucien Favre has hinted the 20-year-old could start against Bayern.
On Wednesday, third-placed RB Leipzig host Hertha Berlin in the day’s key game.
Germany striker Timo Werner warmed up with a hat-trick in Sunday’s 5-0 thumping of Mainz.
He had also scored a hat-trick in an 8-0 mauling of Mainz last November.