You’ve seen them on weekend mornings, the long lines of brunchgoers on sidewalks everywhere — the exhausted parents with small children, bleary-eyed late-nighters ready for a hair of the dog, hollandaise addicts. And while Ignacio Mattos embraces the humble fried egg at Estela more than some of his brethren, you’re more likely to find it nuzzling a crisp square of blood sausage than a couple of strips of bacon.