Spring Vegetable Lasagna

Preheat oven to 375 degrees F. Coat a 9-by-13-inch baking dish with butter.

Whisk broth and mascarpone in a medium saucepan over medium-low heat until smooth, about 5 minutes. Add thyme, oregano and salt; remove from heat.

Heat the remaining 1 tablespoon butter in a large skillet over medium heat. Add spinach and cook, stirring, until wilted, 2 to 3 minutes. Remove from heat.

Arrange 4 noodles in the prepared baking dish, slightly overlapping. Top with 1/4 cup of the spinach and 3/4 cup vegetables. Pour on 1 cup of the mascarpone mixture and top with 1/3 cup farmer's cheese. Repeat to make 4 layers. Cover with a piece of foil coated with cooking spray.

Bake the lasagna for 25 minutes. Uncover and bake until the edges start to crisp, about 15 minutes more. Let stand for 10 minutes before serving.