Parboil the cauliflower in salted water for 8-10 minutes, until soft on the outside but still firm inside, then carefully place on a sieve so it stays whole.
While it cools, mix the braised rice with the ground roasted veal.
With a sharp spoon, scoop out a hollow from the center of the cooled cauliflower, and pack the rice-veal filling firmly into the hollow.
Place the stuffed cauliflower in an oven-safe dish, drizzle with the melted butter and the sour cream, and sprinkle the top with breadcrumbs.
Bake in a preheated oven at 190°C for 20-25 minutes, until the top is a nice golden brown, and serve sliced, hot.
Based on: Malatinszky Fanny szakácskönyve (a classic Hungarian cookbook), modernised. Calories and protein are estimated.