Heading to Germany Sagen was able to boast two third-place finishes, but with these coming in the opening two rounds of the campaign she was looking to bounce back in style after failing to reach the podium in the subsequent three events.
And the 27-year-old did so in style as she racked up 224.9 points to take the win, just 0.6 ahead of second place Iraschko from Austria.
The victory propels Sagen to joint fourth in the overall standings, level on 321 points with American Sarah Hendrickson.
Japan's Sarah Takanashi holds on to the overall lead despite finishing fourth in Germany, but the gap to second-place Iraschko is now 100 points, with France’s Coline Mattel in third overall after claiming the final podium spot.