Start by bringing a large pot of salted water to a boil. Add the medium pasta shells and cook according to the package instructions for al dente. Drain and set aside, reserving a cup of the pasta water in case you need to thin the sauce later.
Heat the olive oil in a large skillet over medium-high heat. Add the ground beef, breaking it apart with a wooden spoon. Cook until it's browned and cooked through, usually about 5–7 minutes. Drain any excess fat before moving to the next step.
Add the chopped onions to the skillet with the beef and cook until translucent, about 2–3 minutes. Throw in the minced garlic and sauté for an additional minute, stirring continuously to prevent burning.
Pour the beef broth into the skillet, followed by the heavy cream. Stir well to combine. Bring the mixture to a gentle simmer, reducing the heat to low. Allow it to simmer for 5 minutes, letting the flavors meld and thicken slightly.
Sprinkle the shredded cheddar cheese into the sauce gradually, stirring until fully melted. Add the cooked pasta shells to the skillet, tossing everything together. If the sauce is too thick, use some reserved pasta water to adjust the consistency.
Taste and adjust the seasoning with salt and pepper. Transfer the creamy beef shells to a serving dish. Garnish with freshly chopped parsley for an added touch of freshness and color. Serve hot and enjoy!
Notes
Store any leftovers in an airtight container in the refrigerator for up to 3 days. Reheat gently to maintain the texture and flavor.