1. Snap off the woody end of the asparagus. Use a vegetable peeler to cut it into long, lengthwise slices. Set aside in a large bowl.
2. Using a mandoline, slice the radishes, zucchini, and fennel. Next julienne the radish slices. Combine with the asparagus.
3. Add grapefruit segments and tarragon to same bowl. 
4. Whisk together the oil, vinegar, Dijon mustard, maple syrup, and grapefruit zest in a small bowl. Season with salt and pepper. 
5. Pour vinaigrette over the vegetables and set in the fridge to marinate for at least 30 minutes. 
6. Transfer to a serving dish and garnish with microgreens.

Chef’s secret

If the asparagus is too thin to slice with a vegetable peeler, cut it in half lengthwise.