Alexa and mqtt publish

Hello,

I would like to control my curtains via Alexa command.
I have setup Alexa and I can control my curtain via mqtt publish call service.
What is the best way to tell alexa to send mqtt command ?
Create input boolean, script or virtual switch?
This is my configuration now. I have no entity .

type: grid
cards:
  - type: button
    tap_action:
      action: call-service
      service: mqtt.publish
      service_data:
        topic: RF/cmnd/sonoff_RF_bridge2/Backlog
        payload: >-
          RfRaw AA B0 37 06 08 12DE 05D2 02BC 2A  55, rfraw 0
      target: {}
    name: curtain open
    icon: hass:window-open
    show_state: false
    show_icon: true
    show_name: true
    icon_height: 60px

thank you