Why are beef eye of round roasts notorious for being tough?

Question

I'm cooking one for the significant other's family. They chose the meat. I'm used to more roast friendly cuts. Most of the recipes i've seen recommend that it be cooked high and fast. But, i don't want it to be pink throughout the whole center (although some is okay).

Answer 1

Eye of Round roast was really made for cooking to a meduim rare stage, I would reccomend cooking it to 140 and taking it out, If you dont want the pinkness of the meat, get an au'jus to dip the slices in to further cook it.
Always slice Eye of Round thin to get maximum tenderness from it.

Answer 2

The eye of round has virtually no fat. Tke a look at a prime rib roast sometime and notice the marbling, the fat that runs all through the cut. The most tender beef (with the exception of the tenderloin, where filet mignon comes from), is either well-marbled or right next to the bone. The eye of round is neither. It's not good as a roast. It's best thinly-sliced in steak sandwiches, where the slices can be seared at high temperature on both sides to keep the juices in. A tender eye of round is cooked slowly in liquid and turns out well-done. It will fall apart rather than slice well. If everyone wants it to cut like a steak and look like a steak, with medium to medium rare pinkness, the chances of it being tender are slim.