Here’s a tip I read in a Chinese cookbook:
To tenderize 1 pound of thinly-sliced round steak, knead in a mixture of 1/2 teaspoon baking soda combined with 3 tablespoons of HOT water. Let stand about 20 minutes or so, then cook the meat according to your recipe. Don’t overcook.
This enables you to use round steak instead of more expensive meat in stir-fries that call for beef.