Add garlic cloves and salt to food processor and pulse until minced and mixed.
Add a spoonful of mayonnaise, or a spoonful of a previously made batch of toum, then mix further. This helps to form a stable emulsion.
Set the food processor to its low setting, then begin pouring ½ cup (112.5mL) of oil into the drip attachment. Go slowly to make sure that a stable emulsion begins to form. Allow the oil to drain from the drip attachment into the emulsion.
Once the oil has drained from the drip attachment, add 2 tsp. of lemon juice. Continue blending until smooth.
Alternate between ½ cup of oil and 2 tsp. of lemon juice until both are gone.
Add optional extra flavorings between the end of step 3 and the beginning of step 5.
Spoon into a food-safe container and store in the fridge covered only in a paper towel for about the first 12 hours. This helps pull excess moisture out.
After 12 hours, put airtight lid on food container.