Ottolenghi's Mushroom Lasagna

Yotam Ottolenghi's new cookbook, Plenty, is absolutely terrific. I'm a long-time fan of Yotam- the London restaurateur , Guardian columnist and cookbook author. His cauliflower cumin fritters with lime yogurt dressing are a staple in our house. And this is another recipe I really enjoyed. I’ve posted a mushroom lasagna recipe before, but I felt compelled to add this one too.

This lasagna is definitely not for anyone who is lactose intolerant or who otherwise has an aversion to dairy. It contains 5 cheeses (Italian Fontina, Feta, Ricotta, Parmesan and Gruyere), lots of mushrooms, in addition to fresh herbs …which makes this cheesy gooey mushroom lasagna the ultimate comfort food that is perfect for winter.

Mushroom Lasagna (Courtesy of Plenty: Vibrant Recipes from London's Ottolenghi)
Serves 8
1 1/4 oz dried porcini mushrooms
1 3/4 cups lukewarm water
5 tablespoons unsalted butter
1 tablespoon thyme leaves
1 3/4 pounds of mixed fresh mushrooms, sliced if large (I used portobello, cremini, and white)
2 tablespoons chopped tarragon
4 tablespoons chopped parsley
salt and white pepper (I used black because that's what I have in the spice rack)
5 tablespoons unsalted butter
1 small shallot, chopped
scant 1/2 cup all-purpose flour
2 1/3 cups milk
13 fl oz ricotta
1 large egg
5 oz feta, crumbled
6 oz Gruyere, grated
1 pound dried spinach lasagna (I used regular lasagna noodles. I wasn't able to find spinach.)
5 oz fontina cheese (or mozzarella), grated
1/2 cup grated Parmesan

   Preheat the oven to 350 degrees.  Cover the porcini with the lukewarm water and leave to soak for 5 minutes.  Drain in a sieve set over a bowl, squeezing the mushrooms to remove all the liquid; reserve the liquid.
   Melt the butter in a large heavy-based saucepan.  When foaming, add the thyme, porcini and fresh mushrooms.  Cook for 4 minutes, or until the mushrooms have softened and exuded some of their liquid, stirring occasionally.  Off the heat, stir in the tarragon, parsley and some salt and pepper.  Transfer to a bowl and set aside.
   Use the same pan to make a béchamel.  Put the butter and shallot in the pan and cook on medium heat for about a minute.  Add the flour and continue cooking, stirring constantly, for 2 minutes; the mix will turn into a paste but shouldn't color much.  Gradually whisk the milk and porcini soaking liquid, leaving any grit in the bowl.  Add 1/2 teaspoon salt and continue whisking until boiling.  Simmer on low heat, stirring constantly, for about 10 minutes, or until the sauce is thickish.  Remove from the heat. 
   In a small bowl mix together the ricotta and egg, then fold in 3 tablespoons of béchamel and the feta.  Add the Gruyere to the remaining béchamel in the pan and stir well to get your main sauce.
   Pour boiling water over the lasagna noodles (do this a few at a time so they don't stick together) and soak for 2 minutes; remove and dry them on a tea towel.
   To assemble the lasagna, pour one-fifth of the sauce over the bottom of an ovenproof dish that is about 10x14 inches.  Cover with lasagna noodles.  Spread one-quarter of the ricotta mix on top, scatter over one-quarter of the mushrooms and sprinkle with one-quarter of the fontina.  Make three more layers in the same way, then finish with a layer of pasta covered with sauce.
   Sprinkle the Parmesan on top and cover loosely with foil (don't lay it directly on the surface of the lasagna).  Bake for 40 minutes, or until the sauce is bubbling around the sides.  Lift the foil and bake for a further 10 minutes, or until the top turns golden.  Remove from the oven and leave to rest for 10 minutes before serving.
Serve this with an arugula and tomato salad!