In a large skillet, heat 2 tbsp olive oil over high heat. Add in the fennel, cut side down, lower heat, and cook for 1-2 minutes. Add in the white wine, cover pan with lid, and cook for 5-7 minutes (depending on the size of the fennel). When the fennel is al dente, remove the lid, turn up the heat, and caramelize the bottom of the fennel until brown. Remove fennel from pan, season with salt, cool slightly, and cut into small wedges.