Zest and juice lemons, mince garlic, and grate parmesan.
Heat olive oil in skillet over medium heat until shimmering.
Add garlic; cook 30 seconds until fragrant, not browned.
Pour in white wine (optional) and let bubble for 1 minute.
Add heavy cream and bring to a gentle simmer.
Stir in lemon zest and juice gradually.
Reduce heat; whisk in parmesan cheese in small handfuls.
Stir until smooth and creamy; season with salt, pepper.
Add parsley and red pepper flakes.
Toss with pasta, chicken, or vegetables. Serve hot.