Step down transformer vs Electronic voltage regulator for appliances between 220v to 110v
Your cooker is described as:-


  America’s most loved multi cooker, built with the latest 3rd
  generation technology, the microprocessor monitors pressure,
  temperature, keeps time, and adjusts heating intensity and duration to
  achieve desired results every time.


It may use phase control (like a light dimmer) to control cooking power. This would be done with an SCR or TRIAC, which delays switching power to the heater until part way through each mains cycle. Alternatively it might use 'zero-crossing' switching, which lets through a proportion of full mains cycles to vary the average power. 

The THYEISTORELETEONINICVOLTACETTCUATOR probably also uses phase control to produce the heating effect of a lower voltage (another name for SCR is Thyristor). This works well with purely resistive loads such as a heater or incandescent lamp, but not with devices which are expecting a full sine wave input - such as your cooker. 

The step down transformer reduces voltage without changing the waveform, so it should work with most devices. The only potential problem is that countries with 220V mains often run at 50Hz rather than 60Hz. Hopefully the controller in your cooker is smart enough to adjust itself to the different mains frequency. Symptoms of not doing so may include 20% slower timing (eg. cooking for 12 minutes when set to 10 minutes) and incorrect power levels if using phase control.