Remove thicker stems from carrot tops, keeping mostly leaves and some soft stems; discard the rest.

Add carrot tops to a food processor and pulse until finely chopped. Add garlic and pulse a few times more. Add pepitas and pulse again.

With the processor running, slowly drizzle in olive oil until the pesto reaches your desired consistency.

Add Parmesan and pulse a few more times to combine.

Season with kosher salt and freshly ground black pepper to taste, then pulse once or twice to incorporate.