Peel the sunchokes, then cut into even sized pieces, about 1-2 inches. Heat the oil in a pot to medium heat, add the sunchokes, stir to coat with the oil, season with a pinch of salt, and cook, stirring occasionally for a few minutes until they begin to lightly caramelize.
Deglaze the pan with a tablespoon or two of water, put the lid back on, and cook until the liquid is evaporated. Shake the sunchokes around in the pan a bit, the pan should have brown residue starting to build up. Add the birch syrup and more water and cook again.
Continue adding small amounts of water, covering the pan to steam the sunchokes , until they're tender when pierced, about 15 minutes. The sunchokes should be deeply brown and glazed. Toss the sunchokes with the fresh herbs, orange zest and toasted nuts if using and serve.