Begin by bringing a large pot of salted water to a boil. Once boiling, add the spaghetti and cook according to the package instructions until al dente, usually around 8-10 minutes. Drain and set aside.

In a large skillet, set over medium heat, add the cream cheese. Stir gently until melted and smooth, taking about 3-5 minutes.

Once the cream cheese is melted, stir in the cheddar and mozzarella cheeses until fully melted, creating a smooth sauce for about 3-4 minutes.

Add in the Rotel tomatoes, stirring until incorporated. Cook for an additional 2-3 minutes.

Fold the cooked spaghetti and shredded chicken into the cheese mixture, ensuring every piece is well-coated.

Continue to cook on medium heat for an additional 5-7 minutes until heated through and bubbly.

Remove from heat, serve hot, and garnish with extra shredded cheese if desired.