Preheat the oven to 375 degrees F (190 degrees C).

Scrub carrots very well and trim, leaving an inch of the green tops attached and reserving greens. Halve any large carrots lengthwise. Arrange in a shallow, foil-lined roasting pan. Toss with 2 tablespoons olive oil and 1/4 cup maple syrup. Season with 1/2 teaspoon each salt and pepper.

Roast in the preheated oven until tender, stirring once or twice, about 40 minutes.

Meanwhile, wash and trim 1 1/2 cups of reserved carrot greens. Bring water to a boil in a large saucepan. Add greens; cook until just wilted, about 30 seconds. Drain and immediately plunge into a bowl of ice water. Remove and blot dry on paper towels.

Combine carrot greens, parsley, Parmesan cheese, almonds, lemon zest, garlic, and remaining 1 teaspoon maple syrup in a food processor. Pulse to chop. With machine running, drizzle in olive oil until well combined. Season pesto with remaining 1/2 teaspoon salt and 1/4 teaspoon pepper.

Drizzle roasted carrots with a little pesto and serve remaining pesto on the side.