Fresh turmeric is the plant's rhizome, a relative of ginger: thin leather-coloured skin outside, bright orange flesh inside. Compared with the powder it tastes fresher, earthier and slightly peppery.
Grate it straight into the soffritto, vegetable soups, tofu scramble or pasta sauces. Be careful: it stains hands, chopping boards and clothes a stubborn yellow, so gloves help. It keeps in the fridge for a few weeks, or in the freezer, to be grated still frozen.