Another one of those "using vegetables up" ideas:
Mash some garlic and combine with minced onion, finely chopped celery, salt, lemon juice, some white balsamico, and rapeseed oil. Dice a zucchini small (1cm) and microwave it a minute or so to kill the raw taste then stir into the rest. Repeat that process with a fennel bulb. Add diced (1cm) carrot. Add chopped basil, mix well, and let it all stand for a while to marinate. Serve on a bed of lettuce.
Season a piece of sirloin well, cook it to rare in the grill pan, slice thinly after letting it rest, and serve beside the salad.