"increasing the amount of" is correct and it can be used in written English.
Here is an example: Increasing the amount of vegetables in the diet can improve overall health.
You also might consider increasing the amount of mint.
So would increasing the amount of assistance they receive.
Increasing the amount of donepezil hydrochloride increased the sensor output.
Increasing the amount of payroll taxes flowing into the fund would require legislative change, she added.
Not that increasing the amount of money we spend developing software could help.
"The only concern is increasing the amount of people coming into the area".
"We've seen this drive to increasing the amount of spend in departments other than DfID.
Other countries, meanwhile, are increasing the amount of money dedicated to research.
Rainmaking, any process of increasing the amount of precipitation discharged from a cloud.
These drugs work by increasing the amount of insulin produced by the pancreas.
To combat this, try gradually increasing the amount of fiber over a few weeks.
