Preheat the oven to 375 degrees F. Lightly oil a 9×13 baking dish or coat with nonstick spray.

In a large pot of boiling salted water, cook lasagna according to package instructions; drain well.

To make the béchamel, melt the butter in a large saucepan. Whisk in the flour until lightly browned, about 1-2 minutes. Gradually whisk in the milk and cook, whisking constantly, until thickened, about 3-4 minutes; season with salt and pepper, to taste. Spread 1/2 cup béchamel in the bottom of the prepared baking dish.

In a large bowl, combine the chicken, ricotta, pesto, 1 cup mozzarella, salt and pepper, to taste. Lay the noodles flat and spread 1/3 cup ricotta mixture evenly along each noodle. Roll up and place seam side down in the baking dish; repeat with remaining noodles and filling. Top with remaining béchamel and 1 cup marinara and sprinkle with mozzarella.

Place into oven and bake for 25-30 minutes, or until lasagna rolls are heated through and the cheese is beginning to brown.

Serve immediately on a bed of marinara and garnished with Parmesan, if desired.