Just changing the setpoint based on a trigger temperature is easily done in the Alarms webui page as Steve has said. If you want to ramp the pit temperature down based on a food probe until they meet at a target temperature, that is "ramp mode" which is also on the Alarms page. For more complex interactions there are Alarm Scripts (separate webui page). You can do fun things like stepping the temperature up or down as you like with an alarm script. There are some examples of those linked on the top of that page.