The Denver and Chuck Eye come from the Chuck primal. Most breeds of cattle, such as Black Angus, marble primarily in the Rib and Loin primals. Wagyu originated as draft animals and were bred to put on growth in the front of their body (Chuck - shoulder and neck), and Wagyu display exceptional marbling throughout most primals.
Denver (aka Zabuton, McKinney) - One of my personal favorites. Known in Japan as Zabuton for its resemblance to a meditation pillow. Comes from the Chuck under-blade.
Flat Iron - The second most tender steak after Filet Mignon, with more flavor. A thin cut from the shoulder blade. We prefer to cook in a pan.
Chuck eye- 'poor man's Ribeye'. An under-appreciated cut that is actually from the same muscle (longissimus dorsi) as the Ribeye, though it is from the Chuck rather than Rib primal, where the muscle tapers and develops more texture from more frequent use.
Loin & Rib cuts guide
Other beef geek cuts come from the Loin or Rib primals and are fairly uncommon except in high-end butcher shops.
Picanha aka Coullete - a tender and flavorful cut from the Loin, the same primal where the NY Strip and Tenderloin come from. Popular at Brazilian steakhouses, where it is referred to as Picanha.
Bavette- Also from the Loin, imagine a tender and more marbled version of a Flank steak
Ribeye cap aka Lifter steak- Our version isnotthe Spinalis muscle, which would have to be taken off a Ribeye, but rather a cut taken from a nearby muscle. This is one of the most flavorful cuts and pairs extremely well with red wine.