Add the yolks, egg, sugar, lemon juice, zest and salt to a saucepanand whisk until thoroughly dissolved.
Transfer to the stovetop and heat up over medium/low heat, whisking constantly until it thickens up nicely (anywhere from 5-8 minutes).
Remove from heat and whisk in the butter.
Sieve into a mason jar, cover on the surface with cling film and transfer to the fridge until set.
make your dough
Add the water (preferably at room temp), active starter and honey to a large bowl. Using your hands (though some peeps favor a danish hook) mix until thoroughly dissolved.
Add in the flour, poppy seeds, lemon zest and salt and mix with your hands until just combined and the dough is all shaggy (and sticky).
Cover with a kitchen towel and let it rest for 30 minutes.
30 mins later: bulk rise (plus stretch ‘n folds)
Thirty minutes in you’ll want to do a set of “stretch ‘n folds”: grab a hold of the dough, stretch it upwards and fold it down towards the center of the bowl. Rotate and repeat four times.
Repeat three more times every thirty minutes.
Allow to rest for until at least doubled in size (remember that time here is directly influenced by temperature so it’ll vary greatly- anywhere from 5-10 hours)(p.s. I generally let mine go until it almost tripes as I’ve pushed it just until the point that it begins to recede back and it still comes out superb)(and I personally find it easiest to digest).
4-8 hours later: shape
See video for guidance! Lightly flour your working surface, turn the dough out and stretch it out gently (allow it to rest for 10 minutes if it “feels” like it’s resisting)(you’ll know, trust me!). Stretch it out, spread lemon curd, fold the sides in, spread more lemon curd and roll it gently but tightly. You then want to roll it gently against the counter towards you a few times (this creates surface tension, making for a better crust!).
Transfer to a (very well floured or lined) banneton or small-ish bowl and cover with a paper towel, place inside a plastic bag and refrigerate for 12-72 hours (depending on how long you want to proof it for).Or allow to proof at room temperature for about 2 more hours, until it springs back to touch (you literally want to poke it gently, and if it springs back you know you’re golden)(though if it springs back too quickly it’s actually under-proofed)(and, you may’ve guessed it, if it doesn’t spring back at all you’re now over-proofed). i.e. this is why baking a few loafs and poking them around throughout it’s stages is highly suggested.
2 hours later: bake away!
Preheat oven to 450°F/230°C with your Dutch oven inside for 30 minutes (some peeps bake at a lower temperature, say 420°F, it depends a bit on your oven).
Score your loaf and place it in the dutch oven.
Bake lid on for 20 minutes, remove lid and bake for 20 more minutes or until deeply golden brown (if you tap it on the bottom it’ll also sound hollow).
Allow to cool completely if you want it at its best– but 20 minutes will do if you simply can’t hold your horses (and you don’t want to wreck your crumb).p.s. my best suggestion for storing your sourdough is to simply keep it in your bread or Dutch oven (what I do). But investing in a bread tin is neat too!
Video
Notes
*please note that all sourdough recipes on the site are developed around King Arthur's Organic Bread Flour (for consistency sake)(and because its my personal favorite "generic" flour to bake sourdough with)(but I generally also test all the recipes with other heirloom & heritage flours– Hayden Flour Mills makes some of my favorite blends).