-
1
Grate the courgettes on the coarse holes of a box grater. Toss with the 2 teaspoons of salt in a colander and leave to drain for 30 minutes. Working in handfuls, wring the grated courgette firmly to expel as much liquid as possible. The flesh should feel nearly dry and compacted when a handful is pressed.
-
2
In a large bowl, combine the squeezed courgette, cooked rice, beaten eggs, 80 g of grated Gruyère, 2 tablespoons of olive oil, and the minced garlic. Add the chopped parsley, basil, marjoram, and thyme in whatever proportion the herbs are to hand. Season with black pepper; the salt retained from the draining step is generally sufficient. The mixture should be cohesive but still loose — vegetable-forward rather than egg-heavy.
-
3
Oil a shallow gratin dish generously. Pour in the courgette mixture and spread it evenly. Scatter additional grated Gruyère over the surface, distribute the fresh breadcrumbs, and finish with a drizzle of olive oil. The topping should cover the surface in an even, unbroken layer.
-
4
Bake at 180 °C for 35–40 minutes. The gratin is done when the top is deeply golden and crisp, the edges have begun to pull away slightly from the sides of the dish, and the centre, when the dish is tapped gently, is set but yields a faint, slow tremor rather than a liquid ripple.
-
5
Remove from the oven and rest for 10 minutes before serving. The gratin may be served warm or at room temperature; the texture and flavour hold well at both temperatures.