1poundlinguinebroken in half and cooked to one minute less than the package recommends.
4Tablespoonsbutter split in half
1 pound cremini mushroomssliced
2largeshallotsdiced
4garlic clovesminced
1 teaspoonfresh thyme
2Tablespoonsdry sherry
⅓cupflour
4Tablespoonsbutter
2cupswhole milk
1½cupheavy cream
2½cupschicken stock
⅛teaspoon grated nutmeg
3cupsshredded turkey meat
1cupparmigiano reggiano cheese
1cupfrozen peas
¾cuppanko breadcrumbs
¼cupparmesan cheese
3Tablespoonsbuttermelted
¼parsleychopped
salt and pepperto taste
Instructions
Preheat the oven to 400°F and grease a 9x13” pan with butter, making sure to get the corners and sides.
Bring a large pot of heavily salted water to a boil. Snap the linguine in half and cook one minute less than the package recommends for al dente. Set aside.
In the bottom of a large heavy bottomed pot, melt the butter and add in the mushrooms. Cook until a deep golden brown on both sides, stirring occasionally.
Add in another tablespoon of butter and cook the shallots and garlic until they are translucent. Stir in the fresh thyme and dry sherry and cook for another minute, or until fragrant. Remove from the pan and set aside.
In a small pot, heat the whole milk, heavy cream, and chicken stock to a simmer.
While this heats, melt 4 more tablespoons of butter in the original pan and stir in the flour. Cook until the mixture becomes a very light brown and smells toasty. About 2-3 minutes. Add in the ground nutmeg.
Slowly add the broth mixture into the flour and stir to combine. Allow the sauce to simmer until the sauce is smooth, slightly thick, and coats the back of a spoon. About five minutes.
Stir in the parmigiano reggiano cheese until melted and remove from the heat. Fold in the leftover turkey meat, mushroom mixture, parsley, cooked linguine and frozen peas then transfer to the buttered pan.
Melt one tablespoon of butter and stir it into a small bowl filled with the panko bread crumbs and parmesan cheese. Season it with salt and pepper, stir in the parsley, then sprinkle it on the tetrazzini.
Bake for 25-30 minutes or until the sauce is bubbling and the breadcrumb mixture is toasted and golden brown. If the breadcrumbs start to darken too quickly, cover the dish with aluminum foil.
Remove the dish from the oven and allow to rest for at least five minutes before serving. This lets the sauce thicken a bit so it isn't runny.
Notes
To make greasing the 9x13" casserole dish easier, melt one extra tablespoon of butter before browning the mushrooms. Then use a basting brush spoon to transfer it to the dish. Use a towel or the brush to move the butter around and completely coat the inside of the dish.
You can skip bringing the stock, milk, and cream to a simmer before adding it, but it may result in a clumpy sauce. Just make sure to slowly whisk in the liquid constantly.