Toscano Mushroom Manicotti with Spinach Bechamel Bake

So just to be different, I changed the Manicotti in this recipe to turkey breast slices :)  It was wonderful!
Here is the recipe as I saw it in Food and Drink Autumn 2010 - but I highly recommend the turkey (smoked if you can).

Tomato Sauce
1 tbsp olive oil
1 cup diced onion
1 tbsp minced garlic
1 can diced tomatoes
1/3 cup tomato paste

Spinach Bechamel
1 tbsp olive oil
1 bag pre-washed spinach
2 cups whole milk (I used 1%)
1 bay leaf
4 tbsp butter
3 tbsp flour
Pinch of nutmeg
Salt and Pepper

Mushroom Filling
2 tbsp butter
1/4 cup diced shallots
1 lb button mushrooms, finely chopped
1 tbsp fresh lemon juice
Salt and Pepper

8 Manicotti tubes
1/4 lb (125g) Monforte Toscano or Italian Pecorino Toscano, 1 cup grated
1 tbsp shaved almonds

1. Heat oil in a medium pot over medium heat.  Add onion and saute until softened, about 3 to 4 minutes.  Add minced garlic and saute another minute.  Add diced tomatoes and tomato paste and simmer over medium high heat for 10 to 12 minutes or until reduced to a thickened sauce that coats the back of a spoon.  Season with salt and pepper to taste.
2. Grease a 9 x 13 inch casserole dish and spread the tomato sauce over the bottom with a spoon.  Set aside.
3. For Spinach bechamel, heat oil in a large frying pan over medium high heat and add the spinach. Saute 3 to 4 minutes or until wilted and soft.  Cool and squeeze out excess liquid.  Roughly chop and set aside.
4. Heat milk in a small saucepan over medium heat until just bubbling.  Add bay leaf and set aside to infuse for 10 minutes.  Remove bay leaf.
5. Melt butter in a medium saucepan over medium heat.  Add the flour and whisk until smooth, about 2 minutes.  Gradually add the warm milk, whisking constantly, and whisk until all lumps are gone.  Simmer until thickened and creamy and coats the back of a spoon, about 7 to 8 minutes.  Remove from heat.  Stir in nutmeg, then spinach until combined.  Season with salt and pepper.  Cover and set aside.
6. Make mushroom filling by melting butter in a large pan over medium high heat.  Add shallots and sweat for 2 to 3 minutes.  Add mushrooms and cook for about 10 minutes or until there is no more liquid draining from the mixture and it is moist but thickened.  Add lemon juice and season well with salt and pepper.  Set aside.
7. Bring a large pot of salted water to a boil and cook manicotti until al dente, about 6 to 8 minutes or as per package directions.  Remove from water and set aside to drain.
8. Preheat oven to 350F.
9. To assemble the dish:  Using a small coffee spoon, stuff each manicotti about 3/4 full with the mushroom filling (if using the turkey slices place in the middle of slice and roll - now you have a meat manicotti).  Place in the casserole dish on top of tomato sauce, all in a row.  Blanket the manicotti with the spinach bechamel.  Sprinkle pasta with the grated Toscano cheese.  Top with the shaved almonds.
10. Bake for 25 to 30 minutes until edges are bubbling; remove from oven.  Adjust rack to top and raise oven temperature to 500F.  Put casserole back in oven for 2 to 3 minutes or until cheese and almonds turn golden (watch closely so it doesn't burn).

Serves 4 to 6