Denser Sourdough Bread

Ingredients

Combine 227g starter, 340g water, and 362g flour in a bowl. Beat vigorously for 60 seconds.
Cover, allow bowl to rest at 72F for four hours. Refrigerate overnight, at least more than twelve hours, and up to 20 hours.
Add the remaining 241g flour, citric acid, and the salt. Knead well to form a smooth dough. If using a stand mixer and a dough hook, knead on a low speed for about five minutes.
Allow the dough to rise in a covered bowl at 72F. Turn the dough out on a surface every 90 minutes or so and knock back the gas gently, returning it to the bowl. Rise for a total of about five hours.
When shaping the loaf, achieve an appropriate surface tension using a roll method to ensure consistent results.
Place the loaf on parchment paper in a shallow bowl about twice its diameter. Put the loaf, in the shallow bowl on parchment, in a garbage bag (preferably clear) or bin liner. Inflate the garbage bag or bin liner gently and tie it off - you're not looking to make a taut balloon here, you just want enough air in the bag to keep it away from the dough.
Allow the loaf to rise for between 2 and four hours. Preheat the oven and cloche to 450F when appropriate.
Dust a loaf with flour, slash with a scissor, and transfer to cloche using peel.
Bake 20min with the cloche closed.
Bake 20min with the cloche lid removed.
Check bread for temperature > 204 F using an instant thermometer inserted 0.5" into the center-bottom of the loaf. Bake a little longer if temperature not yet reached.
Cool bread on rack.

You can add 2T dry rosemary, or more fresh, to make a rosemary sourdough. Add before kneading.
You can mix in 2T roasted garlic paste to make a garlic sourdough. Add before kneading.
You can mix in a head (or two) of roasted garlic cloves after the rising and just before proofing. Simply fold the garlic into the loaf while shaping. This is the most highly recommended modification - the roasted-garlic-clove sourdough is wonderful.
You can bake in a cold pot from a cold oven too: let the bread proof in a closed iron or clay pot, lid on. When ready, dust with flour, slash top, and place, lid on, in a cold oven. Set oven to 450F and begin time on loaf when oven reaches an indicated 450F. The last ten minutes of your bake time should be lid-off.