I love to go to the Union Square Greenmarket to get all of my favorite seasonal produce and a few other treats. One of my favorites has been a buckwheat baguette from a place called Runner & Stone bakery, and I was inspired to try my hand at incorporating buckwheat into a sourdough bread. Buckwheat isn't actually wheat at all - it's a seed that was first grown in Southeast Asia, and you may be familiar with various buckwheat noodles common in different types of Asian cuisine, including Soba noodles. Because it is actually a seed, buckwheat does not contain any gluten, and so I used 25% whole buckwheat flour with 75% whole wheat flour for this recipe to get a balance of the buckwheat flavor with a good rise and structure. Fennel seed is a nice but optional addition - if you don't like fennel, caraway seed would be nice here as well.
100g sourdough starter (fed)
20g maple syrup
125g buckwheat flour (If you can only find whole buckwheat, the seeds are soft enough to be ground to a flour in your blender, like with rolled oats)
375g whole wheat flour (I used milled Turkey Red wheat berries, any whole wheat flour should work)
7g fennel seed
Whisk together the starter, water, and maple syrup until there are no clumps of starter. Add the flours, fennel, and salt and mix everything together until it is well combined.
Let the dough rest for about 30 minutes, then mix the dough and fold it over on itself a few times with a spatula. Repeat this step one more time after another 30 minutes.
Leave the dough, covered, to bulk rise for 8-12 hours. If it is going to be longer (for instance, 24 hours), place the dough in the fridge after 6-8 hours.
After the bulk rise, form the dough into the loaf shape you desire and place in a well floured proofing basket or bowl. Leave the dough for the final proof for 1.5 hours in the bowl or proofing basket, with the seam side up. Preheat your baking vessel when there is 30 minutes remaining on the final proof in your oven at 500 F.
Flip your loaf into the baking vessel, score, and bake covered at 500 F for 10 minutes. After 15 minutes, reduce the heat to 450. After 15 more minutes (25 minutes total), remove the lid of your baking vessel and bake uncovered for an additional 15-20 minutes, until your desired color is reached.
Let cool completely on a wire rack before slicing.