Sourdough Croissants - Attempt #1!

This is my first time attempting sourdough croissants, and my second time attempting croissants in general! I made these into mini croissants which is why they're not as "high".  I think they came out ok! When I first wrapped the dough around the butter slab to begin the lamination process, I realized that the butter slab was too cold so when I attempted to roll it out, the butter started breaking apart between the two layers of dough. 

You ever go into a baking project and the second something goes wrong you're like "oh whatever who cares, it's ruined anyway" and kind of half-ass the rest of the process? That was me upon realizing that the most important part of croissant-making, even distribution of butter, went wrong. So I didn't work as hard as I had intended to going into this.I now really regret that, seeing how decent these turned out. I'm definitely gonna try this recipe again and do it the justice it deserves!

The crumb is okay! They taste pretty amazing. I feel like the sourdough brings out the sweetness in the butter and makes the butter flavor so much more prominent? I didn't use a fancy butter, but it was still the star of this batch. 

Anyway, I developed this recipe based on a few yeasted croissant recipes online. 

Dough: 

470g all purpose flour
250g cold water
60g active starter at 100% hydration
31g dried milk powder
50g sugar
40g room temperature butter
11 g salt

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Butter slab:
320g butter

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Mix the dough ingredients together adding the 40g butter at the end. I used my stand mixer for this but it’d be pretty easy to mix by hand. Flatten out the dough into a disk, wrap in plastic wrap or place in a plastic bag, and refrigerate for 20 hours. Shape the butter slab into a 19cm x 19cm square. Refrigerate till needed. When needed, take it out and let warm up enough for it to be malleable but not soft.

After 20 hours, take the dough out of the fridge and roll into a 26cm x 26cm square. Place the butter slab in the center, at a 45 degree angle to the dough. Fold the four flaps of dough into the center of the butter square. Lightly flour your work surface and the surface of the dough and proceed to roll out the dough into a 20 x 60cm rectangle. Fold letter style (into thirds). Refrigerate for 1 hour, rotate, and repeat two more times.
After the final letter fold, place the dough into the refrigerator overnight. The next day, take out the dough and cut it in half. Roll each half out to a 20 x 55cm sheet. Cut to into triangles, dock, and roll. Place on a baking sheet lined with parchment paper and let proof until the croissants are puffier and a little jiggly. You should also kind of see the layers of butter. Make sure the croissants are proofed in a cool environment. I proofed mine at 70F for around 4 hours. I egg washed them (1 egg, splash of milk, a spoonful of honey) and baked in an oven preheated to 400F and baked for 20 minutes.