Rocher video courtesy of ChefSteps.
A rocher, or one-handed quenelle, is a way to give a beautiful oval shape to butter. Chefs are taught to make a quenelle with two spoons, and that can work well, but by design it creates three curving sides to the shape. For smooth foods, such as butter, a one-handed quenelle is faster and yields a shape with no apparent edges.
A perfect rocher is simple in theory, but it's challenging in practice. The butter must be at room temperature, or a little firmer, so the rocher will form and hold its shape. The food should be uniform, without large voids of trapped air, which would show up as craters in the rocher. The spoon needs to be deep-bowled rather than flat (look for good ones at a thrift store or antique shop). And the spoon must be hot enough to release the rocher, but not so hot that it melts the food. If necessary, warm the bottom of the spoon with your hand to help release the rocher. A rocher will work with any smooth food, such as, ice cream, mashed potatoes, or ganache.
The technique takes practice, but if you spend the time, your dishes will reflect the effort. A rocher makes the simplest of components appear elegant and light.
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