Slow Cooker Cajun Alfredo

Name: Slow-Cooker Cajun Alfredo
Ingredients: 1 lb. boneless skinless chicken breasts; 2 c. heavy cream; 2 tbsp. butter, softened; 0.5 c. low-sodium chicken broth; 1 tbsp. Cajun seasoning; 1 tsp. sweet paprika; 0.5 tsp. onion powder; 0.25 tsp. garlic powder; 0.5 lb. penne pasta; 8 oz. andouille sausage, sliced 1/2-inch thick diagonally; 0.333 c. freshly grated Parmesan, plus more for garnish; 2 c. chopped cherry tomatoes; 4 green onions, thinly sliced