I've the 325 watts its 110V kitchen aid and I

You will need a 'step-down' transformer with a rating of at least 500 watts (~500 VA), a primary designed for 220 Volts and a secondary rated at 110-115 Volts. This type will have four terminals or leads and isolates the input from the output.
There is a non-isolating type called an 'autotransformer' which has one winding with a tap (total of three terminals) roughly in the middle. I use this type for certain devices but it is not as safe as the first-described type.
If you are living in a foreign country that uses the ~220 Volt standard, you can sometimes get one on 'semipermanent' loan from the local utility.