Easy and delicious, taking around 18 hours to make, and perfect for winter breakfasts or holiday gatherings, this Slow Cooker Seville Orange Marmalade is prepared using Seville oranges, lemon juice, granulated sugar, and water. This classic marmalade recipe serves up to 96 tablespoons.

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Slow Cooker Seville Orange Marmalade Ingredients

• 1 kg (2 lb 4 oz) Seville oranges, well scrubbed and halved
• Juice of 1 lemon
• 2 kg (4 lb 8 oz) granulated sugar

How To Make Slow Cooker Seville Orange Marmalade

1. Prepare the Slow Cooker: Start by preheating your slow cooker if required and place a small saucer in the freezer for testing the marmalade’s setting point later.
2. Arrange the Oranges in the Slow Cooker: Place the halved, scrubbed oranges in the slow cooker, covering them with boiling water until fully submerged, then add an upside-down saucer to keep the oranges from floating.
3. Cook the Oranges: Cover and cook the oranges on Low for 8–10 hours. Once finished, leave the oranges to cool in the pot overnight, allowing flavors to develop fully.
4. Prepare the Oranges for Cooking: The next day, lift the oranges out of the pot but reserve the liquid. Quarter each orange, discard any seeds, and thinly slice each quarter for an even texture.
5. Combine Ingredients in a Large Pan: Transfer the sliced oranges, reserved cooking liquid, lemon juice, and sugar to a large, wide pan. Heat gently and stir occasionally until the sugar completely dissolves.
6. Test for Setting Point: Simmer the mixture for 20 minutes, then drop a small spoonful onto the cold saucer. After a few seconds, push the blob with your finger; if it wrinkles, it’s ready. If it doesn’t, continue boiling in 10-minute intervals, testing each time until you reach the setting point, which could take up to 45 minutes.
7. Jar the Marmalade: Once you’ve reached the setting point, ladle the marmalade into warm, sterilized jars. Fill each jar just below the rim and seal immediately for freshness.

Recipe Tips

• Add a Touch of Vanilla: Stir in a teaspoon of vanilla extract during the final simmer for a subtle sweetness that balances the bitter notes of Seville oranges perfectly.
• Choose Ripe Oranges: Select fully ripe Seville oranges as they contain more natural pectin, which helps the marmalade set better and enhances the overall flavor.
• Try a Citrus Blend: Mix in a few regular oranges or a grapefruit to adjust bitterness, especially if you want a milder marmalade with a slightly different flavor profile.
• Use a Food Processor for Slicing: To save time, pulse the orange quarters briefly in a food processor; it speeds up prep without compromising the marmalade’s texture.

Recipe FAQs and Variations

Check out More Slow Cooker Recipes:

• Slow Cooker Apple Pie Rice Pudding
• Slow Cooker Gooseberry Jam
• Slow Cooker Kumquat Jam