1200W, voltage and cycle converter 220 to110
Here's an extract of the specifications accessible at
https://www.chefsteps.com/joule/specs
Performance
1100 watts heating power
Electrical and Operating Requirements
Line voltage 100 to 120 V AC
Frequency 50 to 60 Hz, single phase
You would need a single-phase auto-transformer with the following specifications:
Input 240 V 50 Hz
Output 110 V 15 A
Frequency is not an issue as the specified range is 50 to 60 Hz.