Escarole is a leafy green vegetable, also known as broad-leaved endive that is commonly found in Italian cuisine. It has a slightly bitter taste and is often used in soups, stews, and salads. If you cannot find escarole, there are a few other leafy greens that can be used as alternatives. One option is curly endive, which has a similar texture and slightly bitter taste to escarole. Another option is arugula, which has a more peppery flavor and a crunchier texture than escarole. Alternatively, radicchio, chicory or dandelion greens can be used as a substitute for escarole to give a slightly bitter taste to your dishes.