The humble convenience store egg sandwich became one of Japan's biggest culinary treasures over the past decade, with chefs such as Anthony Bourdain celebrating Lawson’s variety, specifically.

But Seven-Eleven Japan isn't content with just sticking to the iconic, triangle-cut sandwich. It’s recently rolled out a new line of circular sandwiches with savory fillings — the first two arrivals are a tuna-potato and an egg sandwich featuring the same creamy filling found in the much-lauded original. Both varieties (¥127 after tax) come stuffed between two English muffin-like pieces of bread.

They’re both disappointing. The fillings resemble what you would expect on a traditional sandwich, but the problem is the muffin isn’t nearly as fluffy as your typical shokupan bread. And while the taste is fine, the bread to filling ratio is completely skewed, making for an uneven, mostly doughy eat. Clearly, sandwiches just shouldn’t be messed with.