Indonesian Mortar and Pestle



This dish-shaped stone mortar and right-angle pestle is the backbone of the Indonesian kitchen.  One of the key elements of Indonesian cooking is the sambal or spice paste.  The pastes are used as a flavoring for a variety of dishes and they are also used as a flavorful condiment.  The Indonesian mortar is the efficient tool used to render the perfect sambal.

indonesian pestle and mortar
making sambal in indonesian mortar, photo by:

The Stone

The Indonesian mortar is made from a hard basalt stone. Although the cobek has a smooth appearance the stone is rough enough to crush and break through the typical sambal ingredients like chiles, garlic, peanuts, coconut and even lemon grass.

The traditional mortar and pestle can also be found made of palm wood. While the wood version is very attractive it is not quite the efficient grinding tool.  Some cooks like using the palm wood pestle with the stone mortar.

palm wood indonesian mortar and pestle
palm wood mortar and pestle image from:  

Preparing The Mortar For Use

A new cobek and ulek ulek should be prepared before it is used for the first time. Always wash both pieces well in warm soapy (unscented) water.

One source suggests wiping a new mortar out with a stale slice of bread or using grated coconut. While this process will remove any loose stones in the mortar we suggest a method that takes a bit longer but prepares the mortar more thoroughly.

Another technique is to season the mortar with a paste made from kosher salt and raw garlic. Place 3 - 4 large, peeled garlic cloves in the center of the bowl with about 2 tablespoons of kosher salt. Use the pestle to mash the ingredients into the surface of the bowl. Allow the mixture to sit in the mortar for a couple of hours or over night. Then scrape out the mixture and rinse the mortar and pestle with warm water and allow to air dry.

How The Mortar Is Used

Ingredient Preparation

Both fresh and dry chiles are used in making sambals. Whole fresh and dried chiles need to be stemmed, cleaned and seeds removed before use. Smaller chiles such as pequin don't require cleaning. Dried chiles are typically re-hydrated before use and fresh chiles may or may not be precooked.

Garlic, shallots and other soft ingredient should simply be peeled. Some larger ingredients such as tomatoes should be cut into medium sized pieces


Some recipes may suggest grinding ingredients in a specific order to facilitate even grinding.  Make sure to refer to your recipe.  Salt may be added in intervals to help break down coarse foods.

Ingredients are crushed together using a firm but gentle up and down motion.  This crushing extracts the most flavor from the ingredients and gives the sambal the traditional texture.  It takes about 3 to 4 minutes of "vigorous work" to create a paste of the proper consistency.

General Care

Make sure to rinse the mortar well after each use and allow to dry before storing.  While you can wash the mortar and pestle in soapy water avoid scented soap which can be absorbed into thes stone.  Excess scrubbing may remove the "seasoning".

Where To Buy

These mortars tend to be very hard to find in the U.S.  We do sell them online at  Because this product is difficult to obtain we may not always have them available.

Featured Recipe

Basic Sambal Oelek


This basic, hot sambal, which has been called the "mother" of all sambals, is also spelled olek or ulek. Since "olek" means hot peppers, I’ll go with that spelling. This sambal goes well with meats and poultry as well as being a perfect condiment to just add heat to your meal. It can also be used as a base for creating other sambals or as a substitute for fresh chile peppers in recipes.

Yield: 1/3 to ½ cup Heat Scale: Extremely hot

Why Foods Taste Better Prepared In a Mortar And Pestle

Grinding ingredients in a mortar and pestle actually extracts more flavor than does fine chopping in a blender or food processor. This phenomena is explained by UC Berkeley chemist David King.
"There's a phrase in physics called 'shear force,' " he says. "When you shear the matrix that encloses the flavor molecules, you release the flavor." The mortar shears ingredients; the blender cuts them into infinite pieces. "Under the microscope, there's a real difference between something that's been sheared and something that's been cut infinitely."


David King Quote -
Book of Tempeh
Southeast Asian Specialties - Konemann


Pestle - Mutu
Mortar - chowet


Barbara Bowman graduated with degree in Foods and Nutrition from San Jose State University. As CEO of she spends most waking hours writing, cooking, eating, gardening and traveling.