In a large pot, melt 1 tbsp of butter. Add shrimp, bell pepper, and garlic powder over medium heat until shrimp are cooked through, about 1-2 minutes on each side. Remove shrimp from the pot and set aside.
Add remaining butter. Once melted, whisk in flour and cajun seasoning. Cook flour for about 1 minute, then add half and half, stirring. When sauce starts to thicken, stir in parmesan cheese, pasta, and shrimp. Cook for an additional 1 minute to warm up pasta and serve.
Click on the time in the instructions to start a timer!