Slice beef into thin slices against the grain and place in a bowl. Add 2 teaspoon cornstarch salt and pepper and mix until combined. Set aside
Slice all you vegetables
Heat oil in a wok or skillet on high heat. Add meat (in batches if needed, you don't want to overcrowd the wok or skillet) and cook 1-2 minutes and remove to a plate. Repeat until all the meat is cooked.
Add onions and peppers and cook 2-3 minutes just until soft, add in snow peas, garlic and ginger cook another 1-2 minutes.