Culinary use of the mortar and pestle goes back several millennia, and the devices would seem outdated when compared with the speed of the electric food processor. Yet, are there not occasions when a mallet is more desirable than a sledgehammer? Nothing elicits flavor more effectively than a mortar and pestle, whether used for grinding whole spices, bruising fresh herbs or smashing garlic into an intensely charged paste. Salad dressing, mayonnaise and aioli emulsify readily with a practiced hand. Authentic pesto (pesto is a form of the Italian verb pestare, meaning to pound or grind) has a more appealing rusticity than the uniform purée produced in a Cuisinart. Mortars and pestles come in an array of shapes and sizes. We favor a large, heavy mortar made of marble or ceramic and a pestle made of wood (count on spending $40 to $60). It’s a good investment, with thousands of years to back it up.