First, in a small bowl mix salt, garlic powder, onion powder, paprika, and black pepper. Pat dry the chicken with paper towels and season it on both sides with the above dry rub mixture.
Place a large skillet over medium-high heat. Add the olive oil and melt the butter. Once the butter has melted, cook the chicken breasts until golden brown on both sides. Remove from heat, and set aside.
In a medium bowl whisk together chicken broth and cornstarch until there are no lumps. Next, add the slurry to the bottom of an 8-quart slow cooker, and whisk in heavy cream, garlic, Italian seasoning, salt, black pepper, red pepper flakes, and paprika.
After that, add the seared chicken into the slow cooker and pour the juices from the pan in which you cooked the chicken. Add the chopped-up sun-dried tomatoes and corn on top and cook on low for 6-7 hours or on high for 3-4 hours.
Transfer the chicken breasts to a plate and add the parmesan cheese to the sauce, stir to combine. Add the chicken back to the slow cooker, cover with sauce and add chopped fresh basil, turn off the heat and serve immediately.