Fill a bowl with 1/2 cup of baking soda. Add 1 tsp. of water at a time to the baking soda until a thick paste forms.
Dampen a sponge in warm water. Scoop up some of the baking soda paste with the sponge, and scrub the inside of the microwave.
Rinse off the baking soda residue with a damp cloth. Wipe the microwave dry with a towel.
Pour undiluted vinegar into a microwave-safe bowl, place the bowl inside the microwave, and close the oven door.
Heat the vinegar on high for four to five minutes. Leave the bowl inside the microwave for 10 minutes after the cooking time.
Wipe the inside of the microwave with a damp sponge.
Fill a microwave-safe bowl with 1 1/2 cups of water. Chop a lemon in half, and scoop out the inside. Place the lemon pulp and peel into the water-filled bowl.
Place 4 cloves in the water, and set the bowl inside the oven. Microwave on high for five to eight minutes.
Leave the bowl in the microwave for 15 more minutes before you wipe the inside of the oven with a cloth.
Repeat the process if needed.