In a large, deep skillet, heat olive oil over medium heat. Add in the Italian sausage and cook for 4 minutes, breaking up the sausage into small pieces as it cooks. Add in the onion, bell pepper and garlic and continue to cook until sausage is cooked through and vegetables begin to soften, approximately another 3 - 4 minutes. Drain, place onto a large plate; set aside.
In the same skillet, over medium heat, add in both cans of diced tomatoes with liquid. Using one of the empty cans, fill it with tap water, add water to skillet. Using a slotted spoon, break up any large pieces of tomato. Bring mixture to a boil, add in the spaghetti, stir together, being sure spaghetti is submerged into tomato liquid. Cook, stirring occasionally, until spaghetti is cooked through and liquid is absorbed, approximately 10 - 12 minutes.
Add in the reserved sausage mixture, olives, artichoke hearts, thyme and basil, mix to combine and cook until heated through, approximately 1 - 2 minutes. Stir in the mozzarella, just until it begins to soften, not melt.
Transfer to serving platter or plate, garnish with additional basil and enjoy!!