Gather and measure all the ingredients.
Place spaghetti into your Instant Pot in a crisscross pattern.
Place trivet in above the spaghetti.
In a large mixing bowl, combine olive oil, ½ teaspoon salt, ¼ teaspoon pepper, ½ teaspoon garlic powder, ½ teaspoon onion powder, and ½ tablespoon Italian seasoning.
Add chicken and adjust until chicken is evenly-coated.
Place chicken on the trivet above the pasta.
Put lid on and pressure on high for 6 minutes.
Allow natural pressure release for 10 minutes, then quick release.
Brush with BBQ sauce.
Cut into small chunks, and set aside.
While still in the strainer, add diced tomatoes to the pasta. Stir, allowing the tomato juice to strain as well.
Pour heavy whipping cream into your empty pot with ½ teaspoon salt, ¼ teaspoon pepper, ½ teaspoon garlic powder, ½ teaspoon onion powder, and ½ tablespoon Italian seasoning.
Saute on high.
Next, add 1 cup shredded cheddar cheese. Stir contents together and allow to cook for 3 minutes.
Add remaining cup of cheese and stir together.
Bring to a boil, stirring often. Allow to cook and thicken for about 5 minutes. Continue stirring often.
Add pasta and tomatoes.
Stir together until pasta is coated with sauce.
Enjoy every bite.