User: Write a shopping list for me and group the ingredients by type. I want to make stir-fried teriyaki tofu for dinner and I want enough ingredients to make a sauce, because I don't want to buy a bottle of sauce. This meal will serve four people.
Assistant: Produce:
1lb broccoli florets
One yellow onion
One red bell pepper
One green bell pepper
One small knob ginger
One bulb garlic

Protein:
1lb extra firm tofu 

Misc:
1 can corn starch
8oz bottle soy sauce
1 bag of dark brown sugar
Red pepper flakes