Slice beef into very thin strips, slicing across the grain. Season with salt, a dash of garlic powder.
Add this to the slow cooker along with the onions and the sauce.
Cook on high for 3 hours or low for 5 – 6
20 minutes before serving, combine the cornstarch and water and add it to the beef. Give it a stir and then add the broccoli and snap peas. Replace the lid, turn to high and leave for another 30 minutes. Serve with rice.