Make the "tuna". Drain the chickpeas, then add them to a mixing bowl and use a masher to break up the chickpeas. You want them in pieces, but not mashed. Mix the remaining "tuna" ingredients together, then add the mixture to the broken up chickpeas and mix well. Cover and set aside. The tuna flavor will get stronger as it sits, so do this step a few hours in advance if you can. 

Make the vegan sour cream and cheddar potato chips by shaking the chips and Low-Sodium Magickal Cheezy Seasoning together in a gallon size bag, then crush them up a bit. Set aside.

Prepare the pasta. Add the salt to the water and bring to a boil. Follow the package directions for how long to cook the pasta, except cook it a little less than is recommended. (For Tinkyada pasta, I cook it three minutes less.) Drain and rinse the pasta. Let it cool before using in your casserole.

Prepare the vegetables while you wait for the pasta water to boil. Melt the vegan butter in a saucepan (I use Earth Balance). Add the mushrooms, carrots, and celery and stir to coat evenly. Add the Magickal Seasoning Blend, mix it in, then cook the vegetables for about ten minutes. The vegetables are ready when all the liquid released from the mushrooms has evaporated. Turn off the heat, stir in the peas, then transfer the vegetables to a large mixing bowl.

Make the cheeze sauce. Cut the cheeze slices into cubes and set them aside for now. Whisk the water, Dijon mustard, miso paste, and Magickal Cheezy Seasoning together. (I keep both the regular and low sodium versions of my cheesy seasoning on hand, but you can use the low sodium one here as well, and add 5.6 g (7/8 tsp) of salt if you are not on a low sodium diet.) Melt the vegan butter over medium-high heat in the saucepan you used for the vegetables. Whisk in the oat or all-purpose flour, then cook the roux for several minutes. Gradually whisk in the unsweetened plant milk (I use Silk Soymilk). Whisk until smooth. Add the cheezy mixture, then whisk to combine. Bring to a low boil while whisking continuously. Reduce the temperature and simmer while whisking until thickened and bubbly. Add the cheeze cubes, and stir until they are melted in.

Add the cheeze sauce to the vegetables and stir together. Add the cooked pasta and fold it into the sauce and vegetables, then add the “tuna” and mix it in gently.

You can cook all of the casserole at once in a 9″ x 13″ pan, or you can divide it into two 8″ x 8″ or 9″ x 9″ pans, and freeze one to bake later. Line the pan with foil if you will be freezing it, and either line or spray the pan that you will be using to bake in now. Add the mixture to your pan(s).

Divide your crushed chips if you are using two pans. Add half to a sandwich baggie if you are freezing half of your casserole. Sprinkle the chips on the casserole you are baking now, then press them lightly onto the mixture.

Bake at 350 degrees Fahrenheit for 40 minutes, until the chips are golden brown and the center is hot and bubbly. Let it cool on a rack for 10 minutes before serving.