Make the Carrot Top Pesto: In a food processor, combine carrot top greens, fresh basil, and toasted pine nuts. Pulse until finely chopped.
With the machine running, slowly drizzle in the olive oil until the pesto is smooth. Add grated parmesan, red pepper flakes, and salt to taste.
Prepare the Croutons: Preheat oven to 350°F (175°C).
On a baking sheet, toss torn ciabatta or sourdough bread with 2 tablespoons of olive oil, minced garlic, salt, and pepper until evenly coated.
Bake for 10-15 minutes, tossing halfway, until the bread is golden brown and toasted.
Assemble the Salad: In a large bowl, toss together thinly sliced carrots, snap peas, watercress (or spinach/arugula), and fresh herbs for 1 minute.
Add a few tablespoons of the prepared carrot top pesto to the salad and toss to coat the vegetables. Stir in the toasted bread croutons.
Serve immediately with the remaining carrot top pesto on the side for an extra flavor boost.