Trader Joe’s Grass Fed Beef

Grass fed beef can seem to be a bit tougher simply because these animals take longer to get to their butchered weight and as you have discovered they don’t carry as much fat.
As the others have suggested cooking slowly and with extra fat is probably one of the simplest ways of ensuring that the meat is tender when you eat it.
If you like your meat underdone then steaks can also be cooked in the European way flash fried very quickly either side. It’s only when you cook the meat right through that you will find it starts to get tough as a general rule.
Tenderizing the meat using a marinade is also something you can do. A very simple marinade is to mix together a cup of vinegar, a cup of water and 3 teaspoons of bicarbonate of soda and just let the meat marinate in that for at least an hour before cooking as gently as possible.
Lastly a tenderization or tenderizing hammer will work wonders as it will tend to break down the longer fibers in grass fed beef or any grass fed meat come to that and allow you to enjoy your food without having to cut it with a chainsaw.
Hope that helps,
Mark
This is the copy of the comment I made on a forum post about grass fed beef