Yes, this 3-pound, seeded, very attractive loaf seems to call for everything but the kitchen sink, but it’s worth it! Not only is it high in fiber, but the blend of seeds and grains lends it a wonderfully nutty flavor, aroma and texture. The boule is baked in a 4- to 6-quart Dutch oven or similar ovenproof casserole dish. A heavy container with a tight-fitting lid works best, as the steam trapped inside the pot helps crisp the crust. Keep in mind that in a very wide-bottomed pot the loaf will spread out and be fairly flat. In a taller, narrower one it will be thicker and have more height (and may take slightly longer to bake through).
Mix dough: Grind rice in a blender or coffee mill (a food processor won't work) until mostly powdery but with some fine bits remaining. Transfer to a 6-quart (or larger) bowl. Thoroughly stir in 2 1/2 cups whole-wheat flour, 2 cups bread flour, oats, wheat germ, 2 tablespoons each pepitas (or sunflower seeds), flaxseed, poppy seeds and sesame seeds, the salt and yeast. Thoroughly whisk 2 1/2 cups ice water and honey in a medium bowl. Vigorously stir the wet ingredients into the dry ingredients, scraping down the sides and mixing just until the dough is thoroughly blended. The dough should be moist and somewhat sticky, but fairly stiff. (The seeds will absorb moisture, stiffening the dough as it stands.) If the mixture is too dry, stir in just enough additional ice water to facilitate mixing, but don't overmoisten. If the dough is too wet, stir in just enough bread flour to stiffen slightly. Lightly coat the top with oil. Cover the bowl with plastic wrap.
First rise: Let the dough rise at room temperature (about 70 degrees Fahrenheit) for 12 to 18 hours; if convenient, stir once partway through the rise. For convenience (and improved flavor), you may refrigerate the dough for 3 to 12 hours before starting the first rise.
Second rise: Remove dough from bowl. Form loaf on parchment paper coated cookie sheet. Allow to rise at room temp for 1 1/4 to 2 1/4 hours, covered with a large bowl never allowing the dough to touch the bowl.
20 minutes before baking: Position a rack in lower third of oven with a 4 - 6 quart dutch oven in it, this is where you will cook the bread; preheat to 475 degrees.
Brush the loaf with egg white and sprinkle the remaining 2 tablespoons shelled pumpkin seeds (pepitas) and 1 tablespoon each flaxseeds, poppy seeds and sesame seeds over the top (it will be heavily coated). Using well-oiled kitchen shears or a serrated knife, cut two 1/2-inch-deep concentric circles in the top of the loaf, one about 2 1/2 inches out from the center, the other 3 1/2 inches out.
Slide dough from cookie sheet into the duch oven, the parchment paper should still be on the bottom of the dough. Bake, covered, on the lower rack until the top is lightly browned, 50 to 60 minutes. Uncover and bake until a skewer inserted in the center comes out with just a few crumbs on the tip (or until an instant-read thermometer registers 204-206 degrees), 15 to 25 minutes longer. Remove from pot as soon as you remove from the oven. Cool on a wire rack for 10 to 15 minutes. Let cool to at least warm before slicing (if you can!)