Stir the warm water (about 40C / 104F) with the honey and yeast in a small bowl. Let it sit 5 to 10 minutes until foamy on top.
In a large mixing bowl, combine the rye flour, bread flour, salt, fennel seeds, caraway seeds, and ground coriander.
Pour the yeast mixture into the flour mix and knead by hand for 8 to 10 minutes, or 5 minutes in a stand mixer, until the dough is shaggy and slightly sticky. Rye dough stays tackier than wheat dough, resist adding extra flour.
Cover the bowl and let the dough rise in a warm spot for 45 minutes, until visibly puffed. Rye dough won't double the way wheat dough does, look for about 1.5x growth.
Punch down the dough and divide it into 4 pieces, about 220 g each.
Shape each piece into a flat round about 18 to 20 cm / 7 to 8 inches across and 1 cm / 0.4 inch thick on a floured surface. Poke a hole through the center with your finger and dock the surface with a fork.
Transfer the rounds to a parchment-lined 33 x 46 cm / 13 x 18 inch sheet pan. Cover loosely and rest 15 minutes while the oven heats to 220C / 430F.
Bake for 20 to 25 minutes, until deep golden brown and the bottom sounds hollow when tapped.
Cool completely on a wire rack, at least 20 minutes, before slicing. Cutting it warm leaves the crumb gummy.