In a small bowl, dissolve the yeast and sugar in warm water and let sit for 5–10 minutes until frothy.
In a large bowl, combine whole-wheat flour, all-purpose flour, and salt.
Add the yeast mixture and 2.5 teaspoons olive oil to the flour mixture and stir to form a dough.
Turn the dough onto a floured surface and knead for about 8–10 minutes until smooth and elastic.
Place the dough in a lightly oiled bowl, cover with a cloth, and let rise in a warm place for 1 hour or until doubled in size.
Meanwhile, heat canola oil in a large skillet over medium heat. Add sliced onions and cook slowly, stirring occasionally, until deeply caramelized, about 20 minutes.
Add minced garlic and fresh thyme leaves to the onions; cook for 2 more minutes. Season with salt and freshly ground pepper.
In another skillet, heat 2 tablespoons extra-virgin olive oil and sauté radicchio, kale, and sage leaves until wilted and tender, about 5 minutes. Season with salt and pepper.
Toast pine nuts in a dry skillet over medium heat until golden and fragrant, about 3–4 minutes. Set aside.
Preheat oven to 475°F (245°C). Roll out the dough on a floured surface into a 12-inch circle and transfer to a baking sheet or pizza stone.
Spread the caramelized onion mixture evenly over the dough, then top with the sautéed bitter greens.
Sprinkle toasted pine nuts over the top and drizzle lightly with extra-virgin olive oil.
Bake the pizza for 12–15 minutes until the crust is golden and crisp.
Remove from oven, slice, and serve warm.