Preheat oven to 400 degrees F. Generously coat a rimmed baking sheet with nonstick spray and set aside.

Cut off the bottom (root) end of the cabbage and place it on a cutting board sitting up so that the flat end is on the cutting board. Cut top to bottom into 3/4- to 1-inch thick slices. Place on the prepared baking sheet. If you have more slices than fit on your baking sheet without touching, divide them between two baking sheets.

In a small bowl, whisk together the olive oil, garlic, salt, and pepper. Brush over one side of the cabbage, then flip the cabbage over and brush the other side. Roast the cabbage for 26 to 28 minutes, or until crispy at the edges and tender in the center. Rotate the pan halfway through baking.

While the cabbage bakes, toast the pecans in the oven: spread the pecans onto a small, ungreased baking sheet. Toast them in the oven with the cabbage until fragrant, about 8 minutes, tossing them once halfway through. Remove the pecans from the oven and transfer immediately to a cutting board. Let cool, then roughly chop.

Sprinkle the roasted cabbage with Parmesan and fresh herbs. Squeeze the lemon over the top, then finish with the chopped pecans. Serve hot.