Chef John's Spicy Kumquat Marmalade

Cut the kumquats in half lengthwise, then carefully remove the white membrane and discard the seeds.

Divide the kumquat halves into smaller pieces, making sure to minimize any large fragments.

Place the kumquat pieces in a saucepan and combine with sugar, water, lemon zest (only using the white portion), freshly squeezed lemon juice, star anise, and a small amount of heat from the cayenne pepper; stir until well combined. Cover the saucepan and let it sit at room temperature for 2 to 3 hours, allowing the fruit to infuse and soften. Alternatively, refrigerate overnight for a more extended infusion period.

Place the saucepan over medium-high heat and bring the mixture to a gentle simmer, stirring occasionally. Gradually reduce the heat to medium and continue cooking, stirring frequently, until the marmalade reaches a thick consistency that holds its shape when a spatula is scraped across the bottom of the pan, requiring about 30 to 40 minutes of cooking time. Monitor the temperature closely and remove from heat once it reaches 215 to 220 degrees F (120 to 125 degrees C). Allow the mixture to cool slightly for 5 to 10 minutes.

Spoon the warm marmalade into sterilized jars, ensuring they are clean and free of any debris. Cover the jars and let them cool to room temperature before refrigerating until thoroughly chilled.