Food processors can handle most of the prep tasks that ordinarily would be carried out with a knife and cutting board, blender, grater, stand mixer, pastry blender and mortar and pestle. Food processors come in many sizes, from machines used for large-scale cooking in professional kitchens to processors that prepare food for one portion, but they all carry out the same basic functions.
Chopping
The main blade of a food processor has an S-shape and is used for chopping. When you put items in the bowl of the food processor and turn it on, the blade spins around and chops them into small pieces. Control the size of the pieces by how long you run the processor, with longer times leading to smaller pieces. Items to chop in a food processor include onions, herbs, tomatoes and nuts. The chopping blade can even grind meat, too.
Slicing
The slicing blade of a food processor slices foods as you drop them into the chute at the top of the processor. Some processors come with blades that slice foods to a few different thicknesses. Slice carrots, cucumbers, zucchini, eggplant and other vegetables in the food processor. Use the food processor to slice apples when making apple pie or other desserts.
Grating
The grating disk of a food processor makes quick work of grating a block of cheese and saves cooks from risking grating their fingertips as well. Other foods to grate in a food processor include carrots, potatoes for hash browns and zucchini for making bread.
Pureeing
Food processors effectively puree all sorts of food, from chick peas to make hummus to tomatoes to make tomato sauce. You can also puree lumpy soups into smooth ones. One consideration when pureeing in a food processor is that many types of processors will leak if filled too high. You can typically only fill the work bowl about halfway when pureeing liquids, unless the processor is especially designed to be leak-proof when filled completely.
Making Doughs
The basic chopping blade on the food processor can incorporate butter into flour when making dough for a pie crust. This process only requires a few pulses of the processor and replaces the task of cutting butter in with a pastry blender. Some food processors also come with a dough blade that you can use to knead bread dough.