01 -
Arrange a rack in the middle of the oven and heat to 425°F. Line a rimmed baking sheet with parchment paper. Finely grate Parmesan cheese on the smallest holes of a box grater (about 3/4 packed cup), or measure out 1 cup store-bought grated. Transfer to the baking sheet and spread into an even layer.
02 -
Peel carrots and trim the ends. Halve crosswise, then halve or quarter each piece lengthwise so they are all about the same size. Place in a large bowl. Pick the leaves from fresh rosemary sprig and finely chop until you have 1 1/2 teaspoons, or measure out 3/4 teaspoon dried rosemary. Add to the bowl.
03 -
Add olive oil, dried oregano, kosher salt, and black pepper to the carrots. Toss until the carrots are evenly coated. Arrange the carrots cut-side down in a single layer on the cheese, spacing them evenly apart.
04 -
Roast until most of the cheese is dark golden-brown and the carrots are tender, rotating the baking sheet as needed, 15 to 20 minutes total. Let cool for 2 to 3 minutes. Garnish with freshly chopped parsley leaves if desired.