Rusk is loaf bread that has been sliced and toasted to a crunchy golden brown. Germans call it "zwieback," which means "twice baked." In France, rusk is known as "biscotte," which is bread baked into a long loaf, sliced and dried in a hot oven. Unflavored rusk once helped feed military troops and is still often given to teething babies. It can also relieve an upset stomach by absorbing excess stomach acids. Many people enjoy rusk topped with jam, cheese or nut butter.
Zwieback From Fresh Bread
Plain rusk and zwieback bread may not be available in all supermarkets, but you can make your own using one of two basic methods. The first involves baking bread using a standard white bread recipe in which the water is replaced with milk. If the recipe calls for an egg, use two; if it doesn't, you can add one. Double the number of loaves the recipe calls for to make shorter loaves. Once the loaves have cooled, cut 1/2-inch slices using a sharp knife. Bake the slices at 250 degrees Fahrenheit until they are a crisp, golden brown with no moisture. Turn them over if you notice uneven browning.
Zwieback From Stale Bread
The second method uses any purchased bread that has begun to go stale. It should be dry enough to easily slice into thin, even pieces, about 1/4- to 1/2-inch thick. Very stale bread, however, can be too hard to cut. Preheat the oven to 350 F, and place the slices on a wire rack and bake until light brown, usually about 15 minutes. Turn the slices if they are not browning evenly. For a sweet rusk, brush the slices with butter and dredge them in sugar before baking.
Although biscotti are made much like zwieback, the end product is different due to the addition of sweeteners and flavorings. These crunchy treats make an excellent accompaniment to hot tea or coffee or dessert wines. You may have to dip the hardest biscotti in a beverage to make them chewable. They are widely available in the U.S., where supermarkets sell packaged varieties in many flavors. Biscotti may contain citrus zest, nuts, spices, such as ginger or cinnamon, and chocolate. Biscotti are often glazed with icing or dipped in chocolate.
To make biscotti, start with a basic biscotti recipe and add nuts -- about 1/2 cup to 2 cups flour -- spices, zest, chocolate or dried fruit. Blend the dough by hand or in an electric mixer, but don't overdo it, or the biscotti's texture will be too fine. Toast nuts before adding to prevent them from getting soggy in the dough. When adding spices, remember their intensity. Add ginger or cardamom in small amounts. Milder spices such as cinnamon or nutmeg can be added more liberally. Slice the cooled logs into individual biscotti using a sharp chef's knife, which will easily slide through the dough.
- The Oxford Companion to Food; Alan Davidson
- Brandt: Brandt Zwieback
- Fine Cooking; Biscotti for Any Time of Day; Emily Luchetti
- PBS Food; Light, Crispy Rusk Is the Perfect Snack; Marc Matsumoto
- Jupiterimages/Comstock/Getty Images