Aris is another good place to get a cheap 'n' greasy breakfast on Roncesvalles. Sadly, long-established places like this are becoming rarer on Roncies, especially after the disappearance of the very-similar Red Flame not too long ago.
Started by a Greek family (not, as with many places around here, by a Polish one), Aris Place is nevertheless focused more on standard greasy-spoon fare, like burgers, steak and eggs, and stuff like that. Not haute cuisine, and certainly not a flashy place, but the value is excellent and great if you're a fan of heart-clogging classics.