Preserved Citrus Paste
Pureeing salt-preserved citrus fruit yields a tart, tangy fridge-friendly condiment. If you need to add juice to fill the jar, use the same type as the citrus. The one exception is if you're preserving oranges: you'll need a more acidic juice, such as lemon, lime or grapefruit. Since you'll be eating the peel, consider using organic fruit, which is less likely to have traces of commonly used pesticides.