If we need to replace Columbus Day with a celebration of a different Italian, perhaps it can be this guy? (Though according to Wikipedia, the origins of tiramisu are a little murkier than this post suggests.)

Italy bids farewell to pastry chef who invented Tiramisù
Roberto Linguanotto, the Italian pastry chef credited with inventing the modern version of the popular dessert Tiramisù, died on Sunday at the age of 81.
wantedinrome.com