Weigh or lightly spoon whole-wheat flour into dry measuring cups; level with a knife. Combine whole-wheat flour, cricket flour, vital wheat gluten, salt, and yeast in a large bowl. Add water; stir well to form a soft dough. Cover loosely, and let stand at room temperature for 16 to 18 hours.
Turn dough out onto a piece of parchment paper; lightly knead dough 2 to 3 times. Shape dough into a ball on parchment, smooth side up. Cut 2 (1/2-inch-deep) slits in top of dough; sprinkle with sesame seeds and hemp seeds. Coat a large bowl with cooking spray; invert bowl, coated side down, over dough. Let rise 45 minutes to 1 hour.
Place a large covered Dutch oven inside oven. Preheat oven to 450° (leave pan in oven as it heats).
Carefully remove Dutch oven from heated oven; remove lid. Remove inverted bowl from dough. Lift dough, on parchment paper, and carefully place dough and parchment into hot Dutch oven. Cover with lid; bake at 450° for 30 minutes.
Carefully remove lid from Dutch oven; bake bread an additional 15 minutes or until crusty on top.