Soften the onion with the spices

• Heat the olive oil in a Dutch oven over medium-low heat.
• Add the onion, red pepper flakes, Italian seasoning, salt and pepper.
• Cook until the onion is tender.

Add the garlic

• Stir in the garlic and cook until fragrant, less than a minute.

Brown the beef

• Add the ground beef with salt, pepper and paprika.
• Break it up and brown it.

Cook the tomato paste

• Make room in the middle of the pan and add the tomato paste.
• Cook it for a few minutes, then stir everything together.

Add broth and cream

• Pour in the beef broth and heavy cream.
• Bring to a low boil.

Simmer the pasta

• Add the pasta shells and stir them in.
• Lower to a simmer and cook until the shells are tender, stirring occasionally.

Melt in the cheese

• Add the sharp cheddar cheese and stir until melted.
• Taste and season with salt and pepper, and toss in the butter if you like.

Serve

• Plate the pasta and garnish with chives.