Top 100 Five-Ingredient Dinners

My fav dish from Carrabba's - even though it was a "side", I always made it my meal. See "note" from Chef Pedro who works/ed at Carrabba's. Cook onion and pancetta in butter for 30-45 mins until pancetta crispy golden and onions caramelized. Proceed with rest of recipe (nix the wine) and cook on medium-low for 30 minutes. Add scant amount of grated romano and save the rest of cheese when serving with the pasta. It's the real thing!

Do I halve the english muffins first? Also it looks like most pictures show a 9x9 or 8x8 dish, but the recipe says 9x13. Is there a difference in how this turns out depending on which dish I use, or is 9x13 to double? Sorry, just trying to get an understanding.