The 22-year-old Austrian followed up Saturday's victory with another gold on Sunday in Hinzenbach to take control at the top of the standings.
Hoelzl posted two jumps of 87.5 metres, earning 251 points, to see off compatriot Eva Pinkelnig by 3.2 points.
Pinkelnig and Marita Kramer both landed the longest jump of the day at 88.5m but it was not enough to overcome Hoelzl.
She now has 1,030 World Cup points, with Norway’s Maren Lundby on 940 and Pinkelnig further back on 859.
Vintage Women's Finals