I agree the slow-roasted tomato sauce was wonderful but 10 oz of baby spinach made the lasagna very watery and the spinach did not get cooked. I will not be making this dish again.
Lasagna with Slow-Roasted Tomato Sauce
From EatingWell: May/June 2012
Slow-roasting the tomatoes gives the tomato sauce for this lasagna recipe an intense depth of flavor—which is then enhanced by the umami in onions, Parmesan and spinach. The lasagna noodles are layered into the lasagna uncooked; the moisture from the fresh spinach cooks them perfectly as the lasagna bakes in the oven.