Step 1

Bring a large pot of salty water to a boil and prepare pasta according to package instructions.

Step 2

While pasta is cooking, prepare the cheese sauce in a medium saucepot by melting the butter over medium heat. Whisk in the flour, salt, and pepper and cook until flour dissolves into the butter, about 60 seconds, whisking frequently.

Step 3

Pour in the milk and bring the mixture to a low boil, whisking occasionally.

Step 4

Add in the shredded cheese and stir until melted; remove from heat.

Step 5

Drain pasta and return to large pot. Pour in the cheese sauce and stir until pasta is evenly coated.

Step 6

Stir the peas into the pasta as well as the tuna and heat until warmed through, about 2 minutes.

Step 7

Divide between four bowls to serve.