Leeks are an allium related to garlic and onions. They taste like an onion but have a slightly richer, milder flavor.
Leeks will store in an unsealed bag in the fridge for up to two weeks.
Leeks can be used in place of onion in any recipe. Just slice them thinly and don’t cook them quite as long. You can use the white and pale green parts. Leeks are also famously delicious in soup – slow cook them in your favorite broth, then blend (or not) for comfort food of the highest order!