Large loans to build infrastructure and public works that employ large numbers (like fucking huge numbers) of people and increase confidence in the government. Massive reform of laws and law enforcement.
Basically you suck all the excess cash, that caused inflation, out of your economy by means of the loan and interest paid.
This will cause deflation in the mid term which would be disastrous for the working class - and that’s why you employ an enormous number of people to develop infrastructure.
That money then flows back into the local economy because these are working class employees, which supports other workers, and prevents or at least mitigates the depression that you normally risk under deflation.
When you’re done you have infrastructure and services you can use to justify taxation (and taxation by methods like tolls), you have an improved (skilled) working class and a healthier currency. You still have enormous loans to pay back but government debt isn’t actually a problem.
Austerity is just a slower and worse method of the above where you end up with no additional infrastructure or skills in your workforce.