This is one of my favorite quotes and I'm glad to see it discussed here.

My favorite interpretation is focusing on the beauty of how even such a mundane thing as a sandwich is a unique experience. Someone made it by-hand, the ingredients have their own backstory in arriving in the present moment, and the taste is greater than the sum of its parts because of all the competing and complementary flavors.

Sandwiches hide in plain sight and even when they aren't great they are unique and will underscore how good your next great one is.