I remember making tuna casserole before going gluten-free, using canned cream of mushroom soup. It was pretty easy and delicious. However, the ingredients in canned cream of mushroom soup are a complete turn off: soybean oil, wheat flour, MSG, etc. So I found a recipe for tuna casserole from scratch and went about gluten-freeing it and here it is:
- 6 Tablespoon of butter, divided
- 1 small onion, finely diced
- 1 stalk celery, finely chopped
- 1 clove of garlic, minced
- 8 ounces of mushrooms, sliced
- 1/4 cup potato starch
- 1 cup milk
- 1 cup heavy cream
- Salt and pepper to taste
- 15 ounces canned tuna
- 1 cup frozen peas, thawed
- 1 cup shredded cheddar cheese
- 16 ounces gluten-free pasta (I use brown rice pasta)
Preheat oven to 375F and grease a medium baking dish. Set aside.
Bring a large pot of water to boil (I add a little salt and olive oil to my water). Add the gluten-free pasta and cook according to the manufacturer’s instructions.
In a large skillet over medium heat, melt 2 Tablespoon of butter and add the onions. Cook until translucent, then add the celery, garlic and mushrooms. Cook until the mushrooms are golden, about 10 minutes. Set aside.
The base of the creamy sauce is a roux. Melt 4 Tablespoon of butter in a medium saucepan and whisk in the potato starch until smooth.
Combine the milk and heavy cream in a measuring cup and gradually add to the roux, while whisking the entire time. Continue to cook for 5 minutes until thickened and the mixture is creamy and smooth. Season with salt and pepper. Set aside.
In a large mixing bowl, stir in together the tuna, peas, mushroom mixture and roux-based sauce. Set aside.
When the pasta is ready, drain and add to the tuna mixture. Gently stir. Pour in the greased baking dish and add cheddar cheese on top.
Bake 25 minutes in the preheated oven. Let cool 10 minutes and serve!