Special equipment: 4 hot half-pint canning jars, canning equipment, a rolling crinkle cutter
Place the oranges in a saucepan with the sugar, 5 cups water, the lemon zest and lemon juice.
Bring the mixture to a boil, then reduce the heat to a simmer and cook, stirring occasionally until the marmalade gels and thickens and a candy thermometer inserted in the marmalade reads 222 degrees F, about 2 hours 30 minutes.
Ladle the marmalade into 4 hot half-pint canning jars, leaving 1/4-inch headspace. Wipe around the edges of the jar and place the lid in the center. Screw on the bands until tight, then place the jars in a canner filled with boiling water. The jar tops should be covered by 1 to 2 inches of water. Process for 10 minutes, then remove and set aside to cool.
Serve the orange marmalade with Hand-Rolled Whole-Grain Crackers.
Hand-Rolled Whole-Grain Crackers:
Preheat the oven to 350 degrees F and place a rack in the center of the oven. Line a large baking sheet with parchment paper or a silicone baking mat.
In the bowl of a food processor, pulse the almonds until finely ground. Then add the flour, salt, nutmeg and cloves and pulse again. While running the processor, add 1/3 cup water and the oil until combined and crumbly. Remove the cracker dough and form into a ball and place on a sheet of plastic wrap.
Roll the dough between two pieces of plastic wrap to 1/8-inch thick. Cut into any shape using a rolling crinkle cutter, and then transfer to the prepared baking sheet, placing the crackers 1-inch apart. Brush some oil on top of the crackers and sprinkle the sesame seeds over the top. Pierce the cracker dough with a fork so they don't puff up. Bake until crisp and golden, 15 to 20 minutes. Transfer to a wire rack to cool. Yield: about 24 crackers
Properly-handled sterilized equipment will keep canned foods in good condition for years. Sterilizing jars is the first step of preserving foods. Jars should be made from glass and free of any chips or cracks. Preserving or canning jars are topped with a glass, plastic, or metal lid, which has a rubber seal. Two piece lids are best for canning, as they vacuum seal when processed. To sterilize jars, before filling with jams, pickles, or preserves, wash jars and lids with hot, soapy water. Rinse well and arrange jars and lids open sides up, without touching, on a tray. Boil the jars and lids in a large saucepan, covered with water, for 15 minutes. Use tongs when handling the hot sterilized jars, to move them from boiling water. Be sure the tongs are sterilized too, by dipping the ends in boiling water for a few minutes. As a rule, hot preserves go into hot jars and cold preserves go into cold jars. All items used in the process of making jams, jellies, and preserves must be clean. This includes any towels used, and especially your hands. After the jars are sterilized, you can preserve the food. It is important to follow any canning and processing instructions included in the recipe and refer to USDA guidelines about the sterilization of canned products.