Cook papardelle pasta to al dente. Reserve 1 cup pasta water. 

In a pan, combine butter and heat until foamy and melted. Stir in minced garlic. Cook until garlic is fragrant, about 45 seconds. 

Pour in lemon juice, cup of reserved pasta water, Italian seasoning, salt, and pepper. Bring to a rapid boil, stirring occasionally.

When rapidly boiling, remove from heat. Whisk in cream, stirring until combined. 

Return to heat and stir in parmesan, whisking constantly to melt cheese into sauce. 

When cheese has fully incorporated into sauce, and sauce has thickened, remove from heat and toss over pasta with lemon slices. 

Serve and garnish with minced parsley and red pepper flakes, if desired.