Step 1

Heat the oven to 200C/fan 180C/gas Heat the stock in a pan until it is boiling and pour in the polenta in a stream, stirring continuously until the mixture thickens. Season well then leave to cool slightly. Press the polenta into the base and sides of an oiled baking tin approx. 25cm × 30cm (or use a 25cm round tin). Bake for 10 minutes.

Step 2

Meanwhile, fry the courgettes in a little olive oil until golden and softened. Add the garlic, cook for a minute, then stir in the mascarpone.

Step 3

Take out the tart, top with the courgette and mascarpone mix and scatter over the parmesan. Put it back in the oven for another 15-20 minutes until it is golden. Add the rocket before serving.