A hearty bread is your reward for flexing your muscles as you knead this dense dough.
Stir warm water, sugar, and yeast in a small bowl until yeast is dissolved. Let mixture stand until foamy, about 5 minutes. Brush a large bowl with oil and set aside.
Place flours, 1 cup dried figs, fennel seeds, and salt in another bowl. Add yeast mixture; bring mixture together with your hands. Turn out dough onto a lightly floured work surface; knead until smooth and elastic, about 5 minutes.
Transfer dough to oiled bowl, and cover loosely with a piece of lightly oiled plastic wrap. Let dough rise in a warm place until almost doubled in bulk, about 1 hour.
Preheat oven to 375 degrees. Turn out dough onto a lightly floured work surface, and knead in walnuts and remaining 1 cup dried figs (be aggressive with the dough to work in nuts and figs). Shape dough into a ball; pull seams in toward bottom to stretch and smooth top.
Brush a baking sheet with oil; place dough in the middle. Loosely cover with a piece of lightly oiled plastic wrap. Let dough rise in a warm place until almost doubled in bulk, about 40 minutes.
Bake until bread is light golden brown, about 30 minutes. Loosely tent with foil, and continue to bake until an instant-read thermometer inserted in the bottom of loaf registers 180 degrees and comes out clean, about 30 minutes more. Immediately transfer loaf to a wire rack; let cool completely before slicing.
Store this bread in a large resealable plastic bag at room temperature for up to 2 days.