Thinly slice, raw asparagus and lightly cooked cauliflower both soak up other flavors but still stay crunchy.
Trim 1 head of cauliflower. Separate the florets and then drop into salted boiling water. When the water returns to a boil, remove the florets and rinse with cold water. Allow to cool.
Meanwhile trim the bases off 1 bunch of asparagus. Use a vegetable peeler or mandoline to make thin ribbons of the asparagus.
Do the same with 1-2 carrots. You want about 1 C.
Clean spring onions and then slice to make 3/4 C. Place in a bowl with 2 T. lemon juice or sherry vinegar.
Slice the cauliflower florets in halves or thirds.
Toss the vegetables with the lemon juice/onion mixture. Sprinkle with salt and allow to marinate for 10 minutes.
Add 3 T. olive oil and more lemon juice to taste.
Wash and spin dry 4 C. lettuce leaves. Toss the lettuce with the marinated vegetables.