Oops, it doesn't look like 'apple pie apple pie day' is a national day..

Other days

ruby

Ruby Day
hot chocolate

Hot Chocolate Day
self care

Self Care Day
lost sock memorial

Lost Sock Memorial Day
boba

Boba Day
cuddle up

Cuddle Up Day
stud

Stud Day
tulip

Tulip Day
believe

Believe Day
law

Law Day