Preheat the oven to 425 degrees F. Line a sheet pan with parchment paper.
To prep the carrots, cut off the leafy tops and peel them. Rinse a generous 1/2 cup of the tops, tough stems discarded, to use in the pesto.
In large bowl, whisk 2 tablespoons olive oil, honey, cumin, 1 teaspoon kosher salt and 1/2 teaspoon black pepper.
Toss the carrots in the marinade. Then arrange them in a single layer on the prepared pan.
Roast the carrots for 25-30 minutes, turning over halfway through roasting until tender in the middle and lightly browned.
While the carrots are in the oven, make the pesto. Combine the garlic, carrot top leaves, parsley, pistachios, parmesan, 1/4 teaspoon kosher salt, 1/4 teaspoon black pepper and lemon juice in a food processor. Finely chop the ingredients. Then with the food processor running, drizzle in 1/3 cup olive oil through the feeder tube until combined.
On the sheet pan, toss the roasted carrots with half the pesto.
Arrange the carrots on a serving platter, spooning on more pesto as desired. Sprinkle with chopped pistachios before serving.