Wash the green asparagus and cut off the lower ends. Cut the asparagus stalks into pieces approx. 2 cm long and cook in salted water until they are firm to the bite. Wash the cocktail tomatoes, remove the stalk if necessary and cut in half. Put the asparagus and tomatoes in a bowl.
Finely chop the red onion. Wash and chop the chives (I used frozen chives). Put onion and chives in a bowl with rapeseed oil, balsamic vinegar, salt and pepper and stir. Add the dressing to the asparagus and tomatoes and fold in. Let the salad stand for about an hour and garnish with grated Parmesan for serving.