Step 1

Preheat your oven to 375 degrees Fahrenheit.

Step 2

Add the rice and stock to a medium-sized pot over high heat. Bring to a boil then reduce the heat to low and simmer for 12 minutes. Remove the pot from the heat and let it sit, covered, for 10 minutes while you prepare the rest of the casserole.

Step 3

Heat 3 cups of the milk in a medium-sized pot over medium-high heat. Once it is hot, but not boiling, mix the remaining ½ cup of milk with the cornstarch and add it to the pot. Whisk it continuously while it thickens then remove the pot from the heat.

Step 4

Add the cheese and whisk until it melts. Stir in the tuna and the juice from the cans. Season with salt and pepper.

Step 5

In a large bowl, mix the croutons with the melted butter.

Step 6

Spread a thin layer of the sauce in the bottom of a 9x11" casserole dish. Top with half the rice, half of the sauce, and half of the peas. Repeat once more then top with the buttered croutons.

Step 7

Bake the tuna casserole for 20-25 minutes, or until the croutons are crispy and browned and the casserole is bubbling at the edges.