Thanks for your feedback! That's a great point about accessibility and color differentiation. A few others have mentioned similar things, about the lettuce and pickles, but also the tomato and red cabbage (red vs purple).
I really liked the 1-pixel-height toppings in the order visualiser, but that does limit the shape variation to distinguish toppings beyond color. You're right though, playability and accessibility should come first; I'll keep that in mind for future games. Thanks again, and I'm glad you enjoyed it :)