Mario: “Hey, Brian… What the hell are you eatin’?”
Brian: “Peanut butter and jelly on white bread.”
Mario: (shaking head in disbelief, muttering) “Effen’ mangia cake.” 
When I was a kid growing up, I knew Italian moms put a lot into the food they made for us, figuratively and literally. At noon, my friends and I at St Mary’s Elementary School got oohs and aahs from some of our more ethnically-challenged classmates. The exotic ingredients, let alone the sheer size and volume of our mama/nonna-prepared lunches, astonished the non-European student body.
The Polish and Hungarian kids knew what it was to have such love-stuffed goodness. They smiled at us and nodded with respect, displaying their own mouth-watering treasure troves.
The Irish, Scottish and English kids… or the ones whose great-grandparents, regardless of nationality or mix of nationalities, immigrated so long ago that their families had been put through a kind of ethnic deflavorizor… merely stared at us with barely concealed envy, then looked with sadness at their butter and peanut butter and white bread sandwiches. These miserable blonde, ginger or red-haired freckled children had no ‘garlic’ left in their veins, if indeed there ever was any in them to begin with.
In the collective Italian imagination, these poor souls never knew what ‘real food’ was like. They were more to be pitied than anything else. Having grown up with tasteless bland fare, when given a choice between a magnificent dinner of minestrone, spaghetti, meatballs, sausages, Italian bread and a variety of cheeses… these sad deprived wretches would just as soon eat cake.
Hence the expression ‘mangia cake’… cake eater.
Mangia cake is neither a racial slur nor is it a term of hatred, exactly. While derisive, derogatory and even somewhat contemptuous in nature, it is more an expression of pity than anything else.
Deep down, we felt sorry for them. “Eh, c’mon! It’s not their fault they’re mangia-cakes. I mean, who’d ever CHOOSE to be that way?”
So for all you cakes out there, and Lord knows there are an awful lot of you… this is a cute YouTube video recorded a few years ago at The Rivoli on Queen Street West in Toronto…
The Doo Wops singing “Mangia Cake Girl”
(You effen mangia cakes!)
 Mangia Cake (also spelled ‘mangia-cake’ and ‘mangiacake’). [Literally, ‘cake eater’]. A derogatory Italo-Canadian term for white people of British (especially WASP) or mixed Anglo-European descent, especially those whose families have been in the country for several generations. Italians would view the typical daily diet of Anglo-Canadians to be based on refined white flour and sugar and concluded these people had a preference for ‘cake’ as opposed to ‘real food.’