Bring 500ml vegetable stock (or water) to a boil and stir in 125g (1 cup polenta). Stir till the polenta thickens.

Pour into a prepared 20cm square baking tin (lined with baking parchment and rubbed with a little vegetable oil over the surface and sides). Refrigerate or freeze till firm.

Turn out onto a cutting board and cut into chips. Coat in olive oil and sprinkle with rosemary salt (use a mortar & pestle to grind some dried rosemary and coarse salt together).

Place on a baking tray and bake at 180c for 25 minutes or until golden, flipping them halfway through.