Use a kitchen scale to measure out your ingredients. That way you will get consistent results.
In the mixing bowl of a stand mixer, combine the Harvest Grains Blend and boiling water. Let the mixture cool to lukewarm, about 20 minutes.
Add the remaining dough ingredients and knead with the dough hook until you’ve made a soft dough, adding additional water or flour as needed. The dough will be slightly sticky, and can depend on the humidity of the day.
Cover the dough in the bowl, and let it rise until it’s almost doubled, about 1 to 1-1/2 hours. I use the oven with just the light turned on, but any warm, draft-free space will do.
Turn the dough out onto a lightly floured work surface, and gently fold it over a few times to deflate it. Shape it into one large round or two small rounds.
Place the rounds on a half sheet baking pan lined with a Silpat silicone mat or parchment paper, and cover it with lightly greased plastic wrap. Let the loaf rise until it’s very puffy, about 1 to 1-1/2 hours. You can also use a round covered baker or Dutch oven..see the Recipe Notes below for more.
Towards the end of the rising time, place a large saucepan filled with water on the bottom of the oven…this creates steam and helps to give the loaves a crusty exterior. Remove the rising bread from the oven if you’re proofing the loaves in there. Preheat the oven to 425°F, allowing at least 20 minutes of preheating before baking to avoid hot spots.
Just before baking, brush or spray the rounds with water and sprinkle with seeds (if using). Use a very sharp knife to make an X on the top.
Bake the bread for 35-45 minutes (see Recipe Notes if using a covered baker).
