Heat butter and olive oil in a large skillet over medium heat until melted and lightly foamy.
Add garlic and cook for 30 seconds, just until fragrant. Do not brown.
Stir in gnocchi and cook for 2–3 minutes, tossing gently so the gnocchi is coated in the garlic butter.
Reduce heat to medium-low and pour in the cream. Simmer gently for 4–5 minutes, stirring occasionally, until the sauce begins to thicken.
Stir in Parmesan cheese, salt, black pepper, and red pepper flakes if using.
Continue cooking for 2–3 minutes, until the gnocchi is tender and the sauce is creamy and coats the gnocchi evenly. Add reserved pasta water or broth as needed to loosen the sauce.
Remove from heat. Taste and adjust seasoning.
Garnish with fresh herbs and serve warm.