1. Preheat your oven to 350°F (175°C).

2. In a large bowl, combine cornstarch and heavy cream to form a smooth paste, then set it aside.

3. Peel and dice the carrot in a separate bowl.

4. Cook the bacon in a large skillet over medium heat until crispy, then remove the bacon from the skillet, leaving the grease behind.

5. Add the diced carrot to the skillet and cook until softened.

6. Pour in the beef broth, white wine, and blackcurrant jelly, stirring to combine, then bring the mixture to a boil.

7. Reduce the heat to low and let it simmer for 10 minutes.

8. Meanwhile, prepare the beef fillet by seasoning it with salt and pepper.

9. Wrap each slice of beef with a slice of bacon, securing it with a toothpick if needed.

10. Place the beef rolls on a baking sheet lined with parchment paper and brush the tops with butter.

11. Place the baking sheet in the oven and bake for 20-25 minutes, or until the beef is cooked to your desired level of doneness.

12. While the beef is cooking, stir the heavy cream mixture into the skillet with the sauce.

13. Bring the mixture to a simmer and cook for an additional 5 minutes, or until thickened.

14. Serve the beef rolls with the creamy sauce spooned over the top and garnish with fresh parsley and rosemary.