Preheat your oven to 180 C (350 F), get out a 9x13 baking dish.
Cook the tortellini per the package instructions, boiling would be the preferred method. Drain.
In a saucepan, melt the butter with the garlic and basil on medium heat. Cook for a few minutes or until fragrant.
Whisk in the flour and season with salt and pepper as desired. Cook and whisk for 1 minute.
Slowly whisk in the milk, bring to a boil while continuously whisking on medium heat.
Remove from heat and whisk in 1 cup of Cheddar and the Parmesan cheeses. Whisk until the cheese is melted and the sauce is smooth.
Add the cooked tortellini, ham, and peas to the 9x13 baking dish, pour the sauce in.
Mix everything together and spread out evenly.
Sprinkle on the remaining Cheddar.
Bake for 20 minutes.
Serve with sides of your choice and enjoy.