Knives are a chef's most essential tools. But they are often
underemployed in the kitchens for most home cooks. A good knife can transform cooking from drudgery into joy.
Practice the techniques and maintenance.
Precisely cut vegetables not only look good, they have an even texture to the bite and will cook uniformly.
Review the basics of the different types of cuts for various vegetables.
But be innovative as well.
A sharp knife handled properly should be your first concern. Mastering any techniques for sizes and shapes will come with practice.