1. Cook the pasta according to package directions until al dente. Drain and rinse under cold running water. Meanwhile, zest and juice the lemon. Slice the celery finely.
2. Cut the zucchini lengthwise into thin slices. Brush with 2 tbsp oil. Cut the peaches in half and remove the pits. Brush the cut sides with 1 tbsp oil. Heat a grill or grill pan without oil or butter and grill the zucchini 4 minutes, turning halfway, or until softened and grill marks form. Grill the peaches, cut side down, 2 minutes.
3. In a large bowl, whisk together the lemon zest, 2 tbsp lemon juice, crushed red pepper, celery and remaining oil. Season with salt (in moderation) and pepper. Add the pasta and spinach and toss to coat. Tear the mozzarella into pieces and slice the prosciutto. Scatter over the salad with the grilled zucchini and peaches.
Per serving: 735 calories, 41g fat, 12g saturated fat, 65mg cholesterol, 957mg sodium, 62g carbohydrate, 6g fiber, 17g sugar, 31g protein