Heat olive oil in large skillet over medium-high heat. Add ground beef and cook WITHOUT moving for 2-3 minutes to create brown crust.
Break up beef with wooden spoon and continue cooking 3-4 minutes until well-browned and crumbled. Season with salt and pepper. Remove beef with slotted spoon and set aside. DO NOT drain the fat!
Add diced onion to beef drippings. Cook 2-3 minutes until softened and translucent.
Add minced garlic and cook 30 seconds until fragrant.
Stir in tomato paste and cook 1 minute to deepen flavor. Add oregano and red pepper flakes, toast 30 seconds.
Pour in beef broth and scrape up all browned bits from bottom of skillet.
Add uncooked pasta, making sure it's completely submerged in liquid.
Bring to a boil, then reduce to a simmer. Cook 10-12 minutes, stirring occasionally, until pasta is al dente and most liquid is absorbed.
Return cooked beef to skillet and stir to combine.
Pour in heavy cream and stir gently. Simmer 2-3 minutes until sauce thickens slightly.
REMOVE FROM HEAT before adding Parmesan cheese. Stir in Parmesan until completely melted and sauce is silky smooth.
Taste and adjust seasoning with salt and pepper.
Garnish with fresh parsley and extra Parmesan. Serve immediately.