Michigan State University Extension
Preserving Food Safely - 01600675
1. Roasting: For roasting over an open fire, use a covered utensil with a long handle. For roasting in an oven, try a temperature of 300 degrees Fahrenheit for about 15 minutes. Experiment a bit with oven setting and length of time to suit your own preference. When properly roasted, the kernel may be removed with a small fork, dipped lightly or completely in melted butter, and salted to taste. CAUTION: Do not roast chestnuts unless you have punctured the shell with at least 1 or 2 holes. If this is not done, the build up of steam pressure within the shell can cause the nut to explode even after they have been removed from the oven. A sharp-pointed instrument such as an ice pick or knife is good for putting holes through the shell. Leaving one nut unpunctured is one way of knowing when the nuts have roasted long enough - when it explodes, the other nuts should be done.
2. Boiling: First cut the chestnuts in half with a sharp knife. Use a rather shallow pan with cover, using only enough water so nuts are not completely covered. Bring nuts to a boil, then reduce the heat and boil for 15 to 20 minutes. Drain, allow to cool a bit, the kernels should come out readily. The longer the nuts are cooked,the mealier the kernels become and the more they will crumble upon removal from the shell.
Chestnuts may also be boiled vigorously in a deeper kettle with more water. After a few minutes, the kernels will begin to fall out of the half shells. Drain, remove the rest of the kernels from the shells and cook as much as desired in another kettle of fresh water.
3. Steaming: Cut chestnuts in half, and try an initial steaming time of 8 to 10 minutes. Drain and cool a bit and remove any kernels which haven't already fallen out. A small fork may then be used to spear the kernels for dipping in melted butter with salt added if desired. Steaming is considered by some to be the best method for an easy removal of the kernel and is probably best for nuts which have dried a bit too much. Steamed kernels may also be added to other recipes.
4. Microwave oven: Use of the microwave oven can give excellent results with the inner skin and outer shell separating easily from the kernel. Results obtained depend on the number of nuts being cooked, the degree of dryness of the nuts, the setting of the oven, and the length of time involved. Cut nuts in half, and place the cut end down on a double layer of paper toweling. For a start, try using 8 medium-sized nuts and a roast setting for 2 minutes. A bit of experimenting is necessary.
Cooked chestnuts may be kept in the refrigerator in jars for a considerable period of time or in the freezer for even longer.