In a cup filled with warm water add the yeast and sugar. Stir and wait at least 15 minute until the surface becomes foamy. In a bigger bowl place the flour then add the warm water/yeast mixture and stir well. When it reaches a stiff consistency knead the dough on a flat surface covered in flour for about 5 minutes. Transfer again in the bowl and let it rise at least 2 hours.
Meanwhile, heat some oil in a skillet over moderately high heat then sauté garlic until golden, about 30 seconds. Add kale, salt, pepper and sauté about 4 minutes. Transfer to a large bowl to cool slightly, about 15 minutes, then stir in olives and capers.
Cut half of the dough and pat into 9-inch round baking pan, covering bottom. Brush with 1 tablespoon oil and prick all over with a fork.
Spread kale filling over crust and spread cheese. Roll out remaining dough into a 10-inch thinner layer. With this dough cover the filling and tuck edge under bottom crust to form a flat top.
Brush top with some oil and bake until golden brown, 15 to 20 minutes.
Run a sharp thin knife around edge of pan. Invert a plate or rack over pan and holding pan and plate firmly together, flip over the pizza onto the rack. Cool 15 minutes before serving. Slide pizza onto a cutting board and cut into wedges.