How To Make Sweet Potato, Polenta and Rosemary Sourdough

My latest bake is this sweet potato, polenta and rosemary sourdough. I remember the last time I used sweet potato in my sourdough bread was at the beginning of my sourdough journey. Both scenarios are the same – I had some old sweet potato left that I had to use as soon as possible before it went off and voila the sweet potato sourdough was born.

I try to use something different or something I haven’t had a chance to use before in my bread. And this time I’m going to try polenta. Growing up in a rice-eating culture, polenta was not something I was familiar with until I moved to Sydney and started working in the kitchen. I learned more about polenta from the staff meal I had or the polenta chips we had on the menu.

People often think polenta and cornmeal are the same. Well, yes and no. Cornmeal can be made from different kinds of corn like white, yellow or blue corn. It is ground into different consistencies: fine, medium and coarse. On the other hand, polenta originally is a dish made from cooked cornmeal, not an ingredient. Nowadays you can find packages labeled “polenta” in supermarkets which refers to the right grind of yellow cornmeal for making a polenta dish. If not available, use coarse or medium ground corn meal instead.

sweet potato, polenta and rosemary sourdough recipe

weight	ingredient	baker’s percentage
450g	baker’s flour (12.5% protein)	90%
50g	wholemeal flour	10%
375g	water	75%
150g	starter	30%
10g	salt	2%
100g	sweet potato (roasted, pasted)	20%
100g	polenta	20%
10g	rosemary (chopped)	2%
total 1245g

Workflow

Day before or on the same day	Prepare sweet potato paste (see notes below)
Day 1
14:30	Autolyse Mix baker’s flour, wholemeal flour and water (save some for later) until a dough forms. Cover with a tea towel and leave aside for 30 minutes.
	Prepare polenta and chop rosemary Boil water and mix 45g polenta (cornmeal) and 65g boiling water until all the water is soaked in polenta. Leave aside to cool down. Chop rosemary into small pieces.
15:00	Add in starter to the dough and mix for 3 minutes until corporated. Add in salt and the rest of the water and continue mixing for another 3 minutes. Lamination: add in sweet potato, soaked polenta and rosemary and fold the dough, transfer the dough to another container.
15:10	Bulk ferment starts. Perform 3 coil fold sets with 30-minute intervals in between in the first 1.5 hours.
21:10	Pre-shape. 622g * 2 Bench rest for 15 minutes
21:30	Final shape Transfer to the fridge for cold proof overnight.
Day 2
8:40	Pre-heat oven and cast iron bread pan/ Dutch oven to max temperature setting.
9:40	Score the bread and bake. 250 degrees, 20 minutes, with lid. 230 degrees, 20-25 minutes, without lid.

Notes

* To make sweet potato paste, simply chop 2 small sweet potatoes into pieces and bake in the oven until soft. (200 degrees, 15-25 minutes depending on the size). Personally I prefer some chunks of sweet potato in my bread so I would use a fork to roughly make it into a paste.

* Some recipes use polenta(cornmeal) as part of dry ingredients and if that’s the case, there’s no requirement of soaking it first. With this recipe, I soak polenta with boiling water beforehand as a soaker. Just like any other inclusion e.g. nuts, seeds or dried fruit, pre-soaking assists in hydrating inclusion and also prevents inclusions from absorbing (stealing) water from the dough.

* One of the benefits of pre-soaking inclusion is that those inclusions will maintain hydrated and promise a soft and moist texture in the final baked goods.

* lamination: before moving into the bulk ferment stage, spread the dough out and add sweet potato paste, polenta and rosemary to the dough. Fold both sides towards the center and fold the dough again from upwards to downwards. (check this post to see a demonstration of how to add in inclusions at notes section)

* Feel free to use other herbs instead of rosemary. Thyme will be a good substitute for this recipe. I chose rosemary because I have easy access to it. There is a rosemary bush in the garden at my unit block. (Fun fact: rosemary can be found everywhere in Inner West Sydney. Go for a walk around the block and I can find new spots of rosemary!)

At the end

This sweet potato, polenta and rosemary sourdough is by far one of the moistest sourdough I have ever made. I love how soft and moist the texture is. In every bite, I taste the rich flavor of rosemary. This recipe is definitely for rosemary and bread lovers!