Fill a small bowl with 1 tbsp. of liquid dish soap and warm water. Wash the rubber flaps on the rim of the garbage disposal flange using a rag dipped in the dish soap solution. Get under the flaps real well to remove the slime that builds up over time.
Place the stopper in the drain and fill the sink 2/3 full with cold water. Squirt 2 tbsp. of liquid dish detergent into the sink while the water is running.
Pull the plug out of the drain and immediately turn on the garbage disposal. The blades of the garbage disposal create a vortex as the water is draining, washing the inside of the disposal. Turn of the disposal prior to the sink emptying completely.
Fill the garbage disposal half way with ice cubes. Cut a whole lemon into four equal quarters with a kitchen knife. Place the lemon into the garbage disposal.
Turn on the disposal for 15 seconds to chew up the ice cubes and lemon pieces. Turn off the garbage disposal and leave the lemon pieces and remaining ice in the disposal for 30 minutes.
Run cold water and turn on the disposal to completely clear the drain. Allow the disposal to run for one minute after the lemon pieces are gone. Turn off the water and turn off the garbage disposal.