1. In a large bowl, mix the juice of an orange and half a lemon, olive oil, and coarsely ground pepper. Marinate the meat and large onions, peeled and cut into quarters.

2. Cut the zucchinis into thick slices.

3. Steam the zucchinis for 4 minutes.

4. In a pan, melt the butter. Add the juice of an orange and half a lemon. In this butter, roll the zucchinis. Remove from heat and set aside. Preheat the oven grill or BBQ.

5. Prepare skewers by alternating beef cubes, zucchinis, and onion quarters. Grill for about 8 minutes, turning once. Season with salt and pepper. Serve with a rice salad.