Seville Orange Marmalade

Seville oranges are here again, much to the delight of any marmalade fanatics, myself certainly included.
So far I've produced two marmalades-- Classic Seville Orange Marmalade and Rich & Rummy Seville Marmalade. The former is just what it purports to be, a purists' marmalade, made using only seville oranges, sugar and lemon juice. The peel is thick-cut and the set is firm. It's bracing and sunshine-y and the perfect thing to wake up to.
What distiguishes the Rich & Rummy from its Classic counterpart is the substitution of half the sugar with dark brown sugar and a generous glug of dark rum to finish it off. The result is a richer, more mysterious preserve-- your nighttime marmalade, if you will. Although it's equally good on your morning toast, this is what I would use to fill crepes or to stir into cake batter, or just eat out of the jar in front of the open fridge in the middle of the night.
Act now! The sevilles aren't around for much longer...