Butternut Squash and Hazelnut Lasagna

I made this lasagna about a year ago for our dinner club and just made it again this weekend for my ILAB friends. It takes a little bit more effort than I usually like to expend on cooking, but it is delicious and well worth it for a special occasion. This time I bought peeled and pre-cut organic butternut squash from Trader Joe's, and it shaved a good 30 minutes of fighting with a knife off the total time for me. But for me, making the white sauce is even more scary than chopping the squash - I'm always convinced it is not going to come together.

The recipe claims to serve 6, but it would have to be 6 starving people with nothing else on the table (it's in a 9x13 pan!). I think 9 really big servings or 12 medium servings is more realistic. One last tip -- just because you have extra filling and you know it is going to be delicious, do not give in to the temptation to pile it up above the top of the pan! The extra will spillover, burn on the bottom of your oven, and set of the smoke alarm. (The sad thing is I should have learned this lesson 12 hours earlier when I was making Molly's delicious pumpkin chocolate chip cake and did the exact same thing!)

On to the recipe (complements of epicurious.com)...

INGREDIENTS

For squash filling:
1 large onion, chopped
3 tablespoons unsalted butter
3 lb butternut squash, peeled, seeded, and cut into 1/2-inch pieces
1 teaspoon minced garlic
1 teaspoon salt
1/4 teaspoon white pepper
2 tablespoons chopped fresh flat-leaf parsley
4 teaspoons chopped fresh sage
1 cup hazelnuts (4 oz), toasted , loose skins rubbed off with a kitchen towel, and coarsely chopped

For sauce:
1 teaspoon minced garlic
3 tablespoons unsalted butter
5 tablespoons all-purpose flour
5 cups milk
1 bay leaf (not California)
1 teaspoon salt
1/8 teaspoon white pepper

For assembling lasagna:
1/2 lb fresh mozzarella, coarsely grated (2 cups)
1 cup finely grated Parmigiano-Reggiano (3 oz)
12 (7- by 3 1/2-inch) sheets no-boil lasagna (1/2 lb)

PREPARATION

Make filling:
Cook onion in butter in a deep 12-inch heavy skillet over moderate heat, stirring occasionally, until golden, about 10 minutes. Add squash, garlic, salt, and white pepper and cook, stirring occasionally, until squash is just tender, about 15 minutes. Remove from heat and stir in parsley, sage, and nuts. Cool filling.

Make sauce while squash cooks:
Cook garlic in butter in a 3-quart heavy saucepan over moderately low heat, stirring, 1 minute. Whisk in flour and cook roux, whisking, 3 minutes. Add milk in a stream, whisking. Add bay leaf and bring to a boil, whisking constantly, then reduce heat and simmer, whisking occasionally, 10 minutes. Whisk in salt and white pepper and remove from heat. Discard bay leaf. (Cover surface of sauce with wax paper if not using immediately.)

Assemble lasagna:
Preheat oven to 425°F.

Toss cheeses together. Spread 1/2 cup sauce in a buttered 13- by 9- by 2-inch glass baking dish (or other shallow 3-quart baking dish) and cover with 3 pasta sheets, leaving spaces between sheets. Spread with 2/3 cup sauce and one third of filling, then sprinkle with a heaping 1/2 cup cheese. Repeat layering 2 more times, beginning with pasta sheets and ending with cheese. Top with remaining 3 pasta sheets, remaining sauce, and remaining cheese.

Tightly cover baking dish with buttered foil and bake lasagna in middle of oven 30 minutes. Remove foil and bake until golden and bubbling, 10 to 15 minutes more. Let lasagna stand 15 to 20 minutes before serving.