Boil egg noodles. In a large pot, bring salted water to a boil over medium-high heat. Add the egg noodles and cook according to the package instructions until al dente. Drain.
Saute onion and garlic. Melt 3 Tablespoon butter in a large cast iron skillet (or oven safe skillet) over medium heat. Add 1 cup minced onions and cook for about 2 minutes and then add in 2 teaspoons minced garlic. Cook until translucent. Whisk 3 Tablespoons flour on top, until lightly golden.
Finish sauce. Slowly stir in 3 cups half and half and simmer until slightly thickened, about 3-5 minutes. Remove from heat and stir in 1/2 cup cheese. Stir until smooth.
Combine. Stir in the cooked noodles, 1 can tuna, 3/4 cup peas, 1 teaspoon Italian seasoning, 1/2 teaspoon salt, and 1/4 teaspoon pepper until well combined.
Topping. In a small bowl, mix 2-3 Tablespoons panko breadcrumbs, 1 Tablespoon melted butter and 2 teaspoons lemon zest. Sprinkle on top of the casserole.
Bake. Bake 20 minutes, or until bubbly. Move to the top rack or broil the last minute if you want a golden top. Garnish with chives if desired.
Notes
Vegetables: You can add in mixed vegetables, if you prefer.Tuna: I prefer the Kirkland brand. You can use two cans if you'd like extra protein (my family likes 1 best). Variation:
Feel free to make the sauce cheesier by adding 1/2 cup extra cheese to the sauce, if desired.
Use whatever cheese you like, such as sharp cheddar, pepper jack or Swiss.
I love to add fresh herbs to the sauce like thyme or parsley if I have it on hand.