‘Jam’ is really something of a misnomer for this seductive purée. It may be perfectly delicious on toast – I wouldn't know. I prefer to treat it as a sort of luxe dessert ingredient (when I'm not eating it straight from the jar). Plainly spooned over best vanilla ice cream, it shows just how exotic ‘simple’ can be. Blended into whipped cream, buttercream, or dense chocolate ganache, it becomes a decadent filling or frosting for crepes, tortes, and roulades. Hilaire Walden (my recipe is adapted from hers in Sensational Preserves) suggests layering it with whipped cream in parfait glasses. I'm of a mind to work it into a bavarian cream for a Christmas charlotte.
’Tis the season, of course, and chestnuts are in markets everywhere. Perfect timing, as this jam is a fine thing to have around for the holidays. It even cans well, and put up in fancy jars makes a lovely gift. The recipe follows, along with some useful tips for buying and peeling chestnuts.
Finding chestnuts is easy; finding good ones requires a little education.
The American Chestnut was virtually wiped out by blight early in the 20th century. The blight (a form of fungus) hasn't been eradicated, but blight-resistant trees are being propagated, both by the American Chestnut Foundation and the American Chestnut Cooperators’ Foundation. Their goal is to reintroduce a vigorous American Chestnut into the wild. Small pockets of growers around the country have established orchards for the commercial production of chestnuts, but their output and distribution is limited (so far; I expect this will change in the coming years).
What all of this means for you is that the chestnuts you find in the market are most likely imported, probably from Italy, maybe from Spain or Portugal, maybe from the Far East. There is nothing inherently wrong these chestnuts, aside from their perishability.
Chestnuts have a high water content and are low in fat, making them more a starchy vegetable than a true nut. Once harvested (and chestnuts are collected from the ground rather than plucked from the tree), they must be treated carefully – kept under refrigeration with proper humidity, in limited piles to prevent organic heat generation. Even so, their ‘shelf life’ is limited, and they are quick to dry out and grow mold.
So even under ideal circumstances, imported chestnuts are of dubious freshness. Add to that the common display method of dumping them into an open basket and leaving them to sit at room temperature, and you can see why finding ‘fresh’ ones might be a challenge. Of course, you may get lucky and find that your market is peddling domestic chestnuts.
There are a few things to look for when buying chestnuts that may spare you disappointment. Fresh chestnuts have a smooth, glossy, plump appearance, and will be heavy for their size. Squeezed between thumb and forefinger, the shell shouldn't give, as the meat will be firm against the inside. If the chestnuts are dull, and if squeezing the shell indicates a void beneath, and especially if there are any signs of mold...walk away empty-handed. If nothing else, old chestnuts can be impossible to peel.
Alternatively, you might avoid any gamble and order chestnuts online from any of a number of growers. I can't vouch for any one in particular – I've never (yet) bought chestnuts online.
Making Chestnut Jam
This is not a particularly difficult recipe, but dealing with the chestnuts makes it labor intensive, and the quantities are not absolute. In the end, the amount of sugar and water used depends on the final weight of the peeled chestnuts.
To make about 4 cups of chestnut jam, start with:
3 lbs. unpeeled fresh chestnuts
2 1/2 cups of light brown sugar
3 cups water
1 whole vanilla bean, halved lengthwise
2 tbsp dark or blackstrap rum
Peel the chestnuts (see ‘Peeling Chestnuts’ below). Weigh the peeled chestnuts, then place them in a large (3- or 4-qt.) saucepan, and for each pound of chestnuts, add: 1 cup light brown sugar, 1 1/4 cup water, a pinch of salt, and the vanilla bean.
Bring to a boil over medium-high heat, stir well, then reduce heat and simmer, covered, until the chestnuts are very soft, even falling apart (about half an hour). Remove from heat and let cool slightly.
Transfer the mixture to a blender or food processor, or use a stick blender right in the pot, and purée until no lumps remain. If you want a perfectly salacious purée, work it through a fine sieve.
Return the mixture to the pot, scrape in the seeds from the vanilla bean, and simmer – stirring often – until thickened (about the consistency of applesauce), then add the rum and simmer for a few more minutes. Taste, and add more sugar or rum if desired.
The jam will keep in the refrigerator, in an airtight container, for about a month, or can be water-bath canned for long-keeping and gifting.
Plain and simple: chestnuts are a pain in the ass to peel, and treacherous, too. A few helpful tips, though, can make the task much less onerous. Most importantly, heat and moisture will be your friends, softening the leathery peel and keeping the inner membrane free of the meat. Make sure you have a sharp knife with an evil tip. There are specially made chestnut knives, their short curved blade well-designed to minimize the potential for slippage and any resulting bodily damage. I have a cheap curve-bladed paring knife that I bought just for chestnut handling, and it serves me just fine. Whatever you use, great caution is advised. The firm attack required to get under and remove the shell can very easily redirect the blade deep into your palm. Best to use careful leverage from the strength of your fingers rather than the muscle power of your wrists. Also, it's advisable to wear a simple pair of rubber dishwashing gloves, both to help prevent slippage and to protect your hands from the heat, allowing you to work the chestnuts very hot when they're apt to be most compliant.
The first step in prepping chestnuts for peeling is opening up the shell. Most sources recommend cutting an ‘X’ in the flat side of the shell. I've found it easier and more effective to make a single sideways cut as in the photo at left, slipping the tip of the knife between the shell and the meat. Next, the chestnuts need to be subjected to heat and steam. I've tried a number of ways – boiling, boiling then microwaving, and just microwaving. By far, the tidiest method is just microwaving. Simply wrap a few (6 or so) in a well-moistened dish towel, place this in a non-metallic bowl, and microwave at medium-high for 3 minutes.
Remove one chestnut and rewrap the rest to keep them hot. Hold the chestnut firmly in one hand and use the knife for peeling. Work the tip of the knife under the shell, then place your thumb over the outside and pull/tear to remove it, in several pieces. The photo at left shows fully and partially peeled chestnuts, along with pieces of the shell and bits of the papery inner membrane that shrouds the meat of the nut. In some cases, the inner membrane will come away with the shell; in some cases it may remain stubbornly attached to the meat of the chestnut, especially if the chestnut is deeply grooved. Be patient, and keep working at the membrane with the tip of the knife.